onal Bureau of Standards

Library, N.K. Bldg

MAR 2 3 ?955

Dcf

ta i i W

Fire Tests of Brick Walls

United States Department of Commerce

National Bureau of Standards

Building Materials and Structures Report 143
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[List continued on cover page iii]
UNITED STATES DEPARTMENT OF COMMERCE • Sinclair Weeks, Secretary NATIONAL BUREAU OF STANDARDS • A. V. Astin, Director

Fire Tests of Brick Walls

S. H. Ingberg

Building Materials and Structures Report 143

Issued November 30, 1954

For sale by the Superintendent of Documents, U. S. Government Printing Office, Washington 25, D. C.

Price 35 cents

Foreword

Brick walls of buildings have been generally recognized as effective means

of restricting the spread of fire and reducing the loss from conflagrations in built- up areas. Their effectiveness depends upon their stability under fire conditions

and the prevention of ignition of combustible materials near or in contact with

the side not exposed to fire. The present paper gives results of a comprehensive series of fire tests con- ducted under controlled conditions to determine the essential properties of

brick walls as fire barriers. Besides walls of the usual solid design, a number

of hollow walls were included with bricks laid flat or on edge to form one or more unfilled spaces between the brick wythes.

The information should be useful in attaining economy with the required

degree of fire safety in buildings where bricks are used for exterior walls and

interior subdividing constructions.

A. V. Astin, Director.
Contents

Foreword ._ 1. Introduction

2. Materials _ 2.1. Brick __

a. Clay bricks

b. Shale brick

c. Concrete bricks

d. Sand-lime bricks

e. Size of bricks

f. Strength and absorption of bricks,

2.2. Mortar r

a. Materials

b. Proportions

c. Strength

2.3. Plaster

3. Test walls

3.1. Design : a. Solid walls

b. Rolok walls

c. Rolok-bak design

d. Rolok-faced design

e. Cavity design

3.2. Size

a. Large walls

b. Small walls

3.3. Workmanship

a. Construction methods

b. Rate of laying bricks

3.4. Auxiliary strength tests of masonry

a. Test specimens

b. Strength of solid masonry

c. Results with the rolok design

3.5. Seasoning of walls

a. Large walls

b. Small walls

4. Testing equipment and methods

4.1. Panel frames

4.2. Furnace equipment

4.3. Loading and restraint

4.4. Furnace fire exposure

a. Furnace control curve

b. Pyrometer mounting

c. Lag and radiation effects

d. Unprotected furnace thermocouples

,

4.5. Determination of wall temperatures

4.6. Calibration of thermocouples

4.7. Deflection measurements

4.8. Hose-stream tests

5. Program of tests

5.1. Solid walls

5.2. Walls of hollow design

5.3. Fire and hose-stream tests

6. Results of fire-endurance tests

6.1. Criteria of fire-endurance limit

a. Limits of surface temperature rise,,

b. Temperature rise within the wall,,

c. Residual temperature rise

d. Lateral deflection

6.2. Results with solid-wall constructions

a. Walls of 4-in. thickness

(1) Temperature-rise limits

(2) Time-temperature curves

(3) Lateral deflections

b. Clay- and shale-brick walls of 8-in. thickness

(1) Surface-temperature limits, _ (2) Wall-temperature limits

(3) Effect of drying at elevated temperatures

(4) Loading, restraint, and lat- eral deflection

(5) Effect of cracks and imperfect joints

(6) Fusion and spalling effects, _

6. Results of fire-endurance tests—Continued

6.2. Results with solid-wall constructions—Con.

c. Concrete and sand-lime brick walls

of 8-in. thickness

(1) Surface-temperature rise

(2) Temperature limits within

wall

(3) Load-carrying ability and

lateral deflections

(4) Cracks and other fire effects,

d. Solid walls of 12-in. thickness

(1) Surface-temperature limits, _ (2) Temperature rise in wall

(3) Lateral deflection

(4) Cracks and imperfect joints,

(5) Fusion of brick and mortar,

.

(6) Failure under load

6.3. Results with walls of hollow designs

a. Hollow walls of 8-in. thickness

(1) Surface-temperature limits. _ (2) Temperature limits in wall. _ (3) Restraint, loading, and lat- eral deflections

(4) Cracks and other fire effects,

b. Hollow walls of 12-in. thickness

(1) Surface-temperature limits, _ (2) Temperature limits in wall,

.

(3) Cracks and other fire effects

,

c. Cavity walls

(1) Temperature-rise limits

(2) Loading and deflection

(3) Cracks and open joints

6.4. Temperature rise after test

6.5. Ignition of cotton and excelsior pads

7. Results of fire and hose-stream tests

7.1. Performance under fire exposure

7.2. Stability and integrity

7.3. Load-carrying ability

a. Walls of 4-in. thickness

b. Solid and all-rolok walls of 8-in. thickness

c. Solid and all-rolok walls of 12-in. thickness

d. Cavity walls

7.4. Other wall designs

8. Effect of fire tests on strength of brick and

masonry

8.1. Compressive strength of bricks

8.2. Transverse strength of bricks

8.3. Absorption ^ 8.4. Masonry strength

9. Summary and conclusions , 9.1. Materials of construction

9.2. Workmanship

9.3. Wall constructions

9.4. Testing procedure

9.5. Conditioning before test

9.6. Fire-resistance periods . a. Theoretical relations

b. Loading and stability

c. Average fire-resistance periods

(1) Clay- and shale-brick walls

of 4-in. thickness

(2) Solid clay- and shale-brick

walls of 8- and 12-in. thickness

(3) Solid concrete and sand-lime

brick walls of 8- and 12-in. thickness

(4) Walls of all-rolok and alter- nate rolok designs

(5) Cavity walls

(6) Walls of other designs

10.

References

Pase

iii

11

112

2

2

3

3

33

33

44

44

4

44

44

4

4

6

6

6

7

77

78

8

9

9

9

9

1010

10

10

11

1111

1111

1112

12

1313

14

1414

14

14

1414

14

14

1415

15

1515

15

15

1623
Fire Tests of Brick Walls

S. H. Ingberg

Fire-endurance tests were conducted of 54 solid and 19 hollow brick walls, supplemented

by 10 fire and hose-stream tests. The fire-resistance limit of 4-in. clay and shale brick walls was found to be about 1 ^ hr, as based on stability under fire exposure, ability to carry load, and to protect combustible

material on the side not exposed to fire. Plaster on both sides increased the limit to 2 )4 hr. For clay and shale brick solid walls of 8-in. thickness, the fire-resistance limit from the above considerations was 5 hr, which was increased to 7 hr when the walls were plastered on

both sides. For combustible members projecting into the walls 4 in. from the unexpo.sed

side, the protection period was 2 hr, and if plastered, 3 hr. With the 12-in. nominal thickness, the fire-resistance limits ranged from 8 to 10 hr, depending upon the fusion temperature

of the bricks, and with 7 hr as the protection period for framed-in members.

For solid 8- and 12-in. walls of concrete and sand-lime bricks, the fire-resistance limits were found 1 to 2 hr higher than for comparable walls of clay and shale bricks. This was

apparently due to the retarding effect on temperature rise in the wall from evaporation of the combined water in the brick cementing material. The fire-resistance limit of 8-in. clay and shale brick walls of the all-rolok design was

2

L

s hr, and with framed-in combustible members, 1 hr. With plaster, these were increased

to 4 hr and 1 )4 hr, respectively. For 12-in. rolok walls, a fire-resistance limit of 5 hr was

indicated, and 2)4 hr as the protection period for members supported in the wall. For the

plastered wall, these were 7 hr and 3M> hr, respectively. For cavity walls of 10-in. nominal thickness, the fire-resistance period averaged about

5 hr, with 1)4 or 2 hr as the protection period for supported combustible members, depending

upon the degree of embedment assumed.

All wall constructions evidenced ability to meet the performance in the fire and hose- stream test required for their respective fire-resistance ratings.

1. Introduction

Brick walls when used as fire and party walls in buildings have a well-established record in restrict-

| ing the spread of fire, although prior to these tests

I there were few data.extant on their performance in standardized fire tests. Information on such

! performance has become necessary in that build-

! mg-code requirements for fire resistance are now

i in considerable part based upon performance tests

; that have been substituted for or supplement

; requirements formerly designated in terms of

material, design, and thickness of walls in given

I situations. In general, this enables a wider choice of materials and design, not only to meet fire-resistance

requirements but also with respect to considerations of economy and other purposes served by the

; construction.

The present series consisted of 54 fire-endurance

tests of solid and 19 of hollow-type brick walls in

a number of designs, and 10 fire and hose-stream

tests of typical solid and hollow-type brick-wall

! constructions. The nominal thickness was in the

range 4 to 12 in. The first tests were begun in 1921 and continued

at intervals thereafter. These tests were made

before the fire-testing procedure had been standardized on all particulars. However, sufficient information was obtained in these and later tests to enable the fire resistance for almost all of the

construction types and designs to be evaluated in terms of performance, using the procedure now

recognized as standard.

2. Materials

2.1. Brick

The walls for the present series of tests were

built of clay bricks from three States, shale bricks

from one, and sand-lime and concrete bricks each

from three sources.

a. Clay Bricks

The clay bricks were made from so-called sur- face clays, the sources and symbol for each being as given in table 1. The brick from Maryland, designated OLM.

was made from a red plastic clay by the so-called

“soft-mud” machine-molding process, and had a gritty surface from dusting the molds with tine sand. The softening point of the burned material was near 1,475° C (2,6S7° F) (cone 17).
I

Table 1 . Strength and absorption of bricks H"

Brick

Wall or test 2

Compressive strength Modulus

of rupture

Absorption

(5-hr. boiling) Type Locality Type and

source symbol 1 On side On edge

Iblin.i l b/in. 2 Ib/in.i Percent

Surface clay - .. Md CLM 1, 11, 14, 15, 38, 54, 64 3,280 2. 560 760 15.6 Do . Md CLM 16, 17 3, 130 1, 960 1 *>10 15 6 Do Md CLM 2, 18 2, 960 2. 940 ’ 920 14 5 Do Md CLM 3, 4, 8, 9, 12, 37, 39, 41, 42, 60 to 63, 65 to 69 - 2, 960 3, 040 890 14 7 Do 111 CLI 19 to 21, 43, 55 to 57 ’ 2, 920 2, 330 1, 180 22 5 Do 111. -. CLI 44 3, 280 3, 350 1 230 16 7 Do . N. Y C LN 70 3. 580 450 20 0 Do N. Y CLN 7, 71, 72 2, 920 420 19 8 W. Va SHW. .. 5, 22, 23, 58 8, 110 6, 400 2. 020 6 5 Do W. Va SHW 6, 59. 6, 450 5. 640 1 570 10 2 Do .. W. Va SHW 10A _ _ 10, 040 7, 410 2 760 5 6 Concrete . N. Y CON 25, 26, 45 2,780 1,530 650 13.5 Do 1).C COD 49 2, 920 2, 290 780 10.8 Do D. C COE 28, 50 3, 350 2, 490 800 Pa__ SLP 29 to 31, 51 4, 630 4. 720 930 16 4 Do D. C . SLD - 31 - 2. 050 1. 690 460 20 7 Do. D. C SLD... 32. 3, 050 2, 550 850 24 3 Do D. C - SLD 35 . 2, 020 2, 000 540 20 8 Do SLO 36, 53 3,600 3, 000 800 14.5

1 These symbols are used throughout the text and tables.

2 Some of the bricks were also used in building walls for fire and hose-stream tests, for which the wall numbers are not here included.

ill

.if

!

\

H

Ml The Illinois brick (CLI) was made by the extrusion “stiff-mud” end-cut process from a calcareous

clay. Its softening point was near 1,145° C

(2,095° F) (cone 01).

The New York, or Hudson River, brick (CLN)

was made by the same process as the Maryland

brick from a surface clay to which a small amount

of powdered coal was added to increase the porosity. The average coefficient of expansion in the

temperature range up to 900° C was about

0.0000068. This comes within the lower range

reported for such material [l]. 1

b. Shale Brick

The concrete brick (COD) from the District ofj

Columbia was made from a damp mix of 1 part of Portland cement to 6 parts of coarse (concrete)

sand, proportioned by volume. The sand, Poto-L mac River, consisted of 50 to 60 percent of quartz,

the rest being micaceous and feldspathic minerals,

some of which carried iron compounds.

The molding by the dry-tamp process was fol- lowed by steam curing at 20-lb/in. 2 pressures for

24 to 36 hr. The concrete brick (COE) was also made in the

District of Columbia of the same type of materials

and concrete mix as the COD brick and cured by

similar process. Shale brick from West Virginia (SHW) was made from a typical shale by the extrusion “stiff- mud” side-cut process. The softening point of the burned brick material was near 1,305° C

(2,381° F) (cone 10).

c. Concrete Bricks

The concrete brick from New York (CON) was made from a mix of 1 part of portland cement to

5 parts of siliceous sand by volume. The sand

contained 60 to 70 percent of quartz, the rest being

micaceous and feldspathic minerals.

In making the brick, the wet mix was contained

in a form 8 ft high, 8 in. wide, and 23% in. long.

Blocks 3% in. high were cut from the base of this column, from each of which 10 bricks on edge were cut. The mix in the form was compacted

by the dropping incidental to the successive

removal of blocks from its base. The bricks were cured for 4 days in moist air heated to normal indoor temperatures, after which

they were stored outside.

1 Numbers in brackets refer to references at the end of this report.

d. Sand- Lime Bricks

The sand-lime brick from Pennsylvania (SLP)

was made with a sand obtained by mixing and

crushing the clean waste from a brownstone

quarry and stone-cutting plant. From 95 to 100 j percent of it passed No. 10 (0.073 in.) mesh; 75 to ] 85 percent, No. 40 (0.015 in.) mesh; and about 20

percent, No. 100 (0.0055 in.) mesh. Chemical

analysis of the sand indicated about 90 percent of

silica, 6 percent of alumina and iron oxides, the

rest being lime, magnesia, soda, and potash.

The high-calcium quicklime used was hydrated

as mixed with about four parts of sand, the mixture

being previously pulverized in a tube mill. More

sand was added in the final mix to give a proportion of 1 part of quicklime to about 17 parts of dry

sand by weight. The brick was molded in machines under high pressure and then hardened

under 30- to 35-lb/in.2 steam pressure for 10 to 11 In. The sand-lime brick from the District of Columbia (SLD) was made with a bank sand containing

about 90 percent of quartz, the rest being largely

2
IF

: orthoclase feldspar. The mix was in the proportion of 1 part of high-calcium hydrated lime to 9

jjparts of sand by weight, the lime being hydrated

at the plant previous to mixing. The bricks v, ere

I {molded by machine under high pressure and then

hardened under 120-lb in.-2 steam pressure for 10 hr. The sand-lime brick from Oliio (SLO) was made

'with a sand consisting of a mixture of siliceous and

(clolomitic minerals. This was mixed with highcalcium lime and enough portland cement to give

I the required strength in the hardening process

{ under steam pressure.

e. Size of Bricks

The average dimensions of the bricks from a

j given source were within % in. of 2/ in. for the

.thickness, within % in. of 3% in. for the width,

'and within % in. of 8 in. for the length, except for

| the sand-lime brick (SLD), which was 2% to 2]4 in.

i thick. 4}$ to 4K in. wide, the average length being

I 8% in. They were all solid without cores or scorning, except that clay brick CLN had a formed

(depression, or “frog”, on one side equivalent to

I [about 15 percent of the volume.

f. Strength and Absorption of Bricks

The types and sources of the bricks are given in

M table 1. together with the numbers of the walls for fire-endurance tests built from each lot. Also

included in this table are average compressive

.strengths determined with half bricks on side or

ledge, the modulus of rupture on 7-in. span, and

ithe water absorption by 5-hr boiling. These

determinations were made in accordance with

i methods given in the standards of the American

vSociety for Testing Materials. The number of

! determinations on which average results are based

(ranged from 5 to 50 or more.

2.2. Mortar

The proportions and strength of the mortar

used for laying up the walls are given in table 2.

a. Materials

The portland cement and lime were obtained

from local dealers and were tested to determine

conformity with accepted standards. Both the

quick lime and hydrate were of the high-calcium

type.

The sand, dredged from the Potomac River,

contained about 95 percent of siliceous minerals,

mainly quartz, the rest being of micaceous and

feldspathic type. In fineness, all of it passed

No. 4 sieve; about 95 percent, No. 16 sieve; 20 to 25 percent, No. 50 sieve; and 4 to 5 percent,

No. 100 sieve.

b. Proportions

Although the proportions are given by volume,

the quantities were obtained by weight. A bag

of portland cement weighing 94 lb and one of

hydrated lime weighing 50 lb were taken as 1 and

\'y

4 ft 3

, respectively. The dry contents of 1 ft 3 of sand was taken as 78 lb, except that for 1:1:6

mortar an 80-lb equivalent was taken. The

amount of mixing water to be used was left to the discretion of the mason but weighed for each

batch of mortar.

c. Strength

The compressive strength of the mortar was

determined with 2-in. cubes, one or more of which

were taken from each batch and stored near the

test walls under similar atmospheric conditions.

The results in table 2 are segregated by age and

also by water content of the mix, where speci- mens were numerous enough to give dependable

averages. The results indicate that, in general, for the

cement-lime mortars there was an increase in strength with age and a decrease in strength with

increase in water content of the mix. The 1 : Iji :6 mortar had lower strength than the 1 : 1 % : 6 mortar,

due apparently to higher lime and sand content. However, the difference probably had no effect on the fire resistance of the walls.

Table 2. Compressive strength of mortar for laying up walls

Type of mortar

Proportion- cement, hydrated lime, and sand Number

of walls Water content 1 of mix

range

Average

age Averagestrength By dry

v. eight By nominalvolumes

Percent Dans Iblin.-

1 Lime _ . _ 0:50:234 0:114:3 3 26.8 to 31.3 62 60 Do 0:50:234 0:114:3 3 26.7 to 30.7 140 55 Cement-lime. ... 94:60:468 1:114:6 8 21.7 to 25.0 64 310

i Do . 94:60:468 1:114:6 12 25.1 to 36.2 71 ISO Do 94:60:468 1:114:6 6 25.1 to 36.2 326 220 Do 94:50:468 1:114:6 6 19.9 to 23.0 (12 340 Do 94:50:468 1:114:6 4 19.9 to 23.0 218 540 Do 94:50:468 1:114:6 25 23.1 to 26.0 r>3 340 Do... 94:50:468 1:114:6 13 23.1 to 26.0 198 450 Do 94:50:468 1:114:6 11 26.1 to 30.6 70 290 Do 94:50:468 1:114:6 3 26.1 to 30.6 186 280 Do 94:40:480 1:1:6 3 23.4 to 25.4 43 550 Cement 94:0:234 1:0:3 2 22.5 to 23.0 61 850 Do 94:0:234 1:0:3 2 22.3 to 23.8 172 800

|

i Based on total weight of dry materials.

3
2.3. Plaster

The lime, Portland cement, and neat fiberecl gypsum plaster with which the sanded plaster was made were obtained from local dealers, and

in pomt of quality passed accepted test requirements. The sand was from the same source and

of the same fineness as used for the mortar. The plaster was proportioned by weight of dry

materials. The compressive strength, as determined with 2-in. cubes taken from each batch

and stored near the test- walls, is given in table 3. The plaster was applied in two coats to a total thickness of 1/2 to 5/8 in. No white-coat finish was applied.

Table 3. Compressive strength of sanded plaster

Propor- Type of plaster

tions, by dry Wall Age Average

strength weight

Days lb/in. 2

1 1:2*4 10A 70 90 Lime... ...

I 1:3

) 1:3 4260

65

54 8025

1 1:3 63 67 60 Cement _ 1:2*4 8 62 740

1:3 9 61 590

1:3 37 67 500 Gypsum 1:3

1:3

61626167 640

920

1:3 66 67 470

1:3 67 98 740

3. Test Walls

3.1. Design

The walls of the present series of tests were of

solid or of hollow types, as shown in figures 1 and 2.

the bond broken vertically. The all-rolok design

indicated by D and F in figure 1 has stretchers

and headers, all on edge. In design G, all-1 stretcher courses alternate with all-rolok courses. In design H, two stretcher courses on edge alter- nate with a bonding comse having bricks laid on

side with two headers for each stretcher.

i c. Rolok-Bak Design

For the 8-in. wall, figure 1, E, a common bond

with bricks laid flat is attained for the facing, the

backing having four stretcher courses on edge per

header course laid with bricks on side. For the

12-in. wall, design J, the same bond is attained

for the facing, and the backing has three stretcher courses on edge alternating with two bond courses, one with headers on edge and the other with

headers and stretchers laid flat.

d. Rolok- Faced Design

As per design Iv of figure 1 , the all-rolok facing is attained for a 12-in. wall with three all-rolok courses alternating with a rolok course having

false (lialf-brick) headers. The backing has

three stretcher courses on edge alternating with

a solid header course of bricks on edge.

e. Cavity Design

In the cavity type, design L in figure 1, two

4-in. wythes with bricks laid flat were tied to- gether with metal ties in every sixth course spaced

2 ft apart horizontally. In the walls of the present

tests, the ties were Z-shaped and of coppercoated steel wire 0.20 in. in diameter.

3.2. Size

a. Solid walls The conventional designs of solid walls are shown in figure 1 (A to C) and of a 4-in. wall

with pilasters in figure 2. The 4-in. walls were laid with vertical joints

broken, that is, with the joint opposite the middle

third of the length of the bricks immediately

above or below them. The wythes of the 8-in. walls and outside wythes of the 12-in. walls were

similarly laid. In the same course the stretchers

in 8- and 12-in. walls were laid with end joints in alinement in some walls, and in others they were

broken. With two otherwise similar walls, one was built to each detail on this particular. There was one header course for every five stretcher

courses.

b. Rolok Walls

With the rolok designs, the bricks in all or the

greater number of courses are laid on edge with

a. Large Walls

The large walls were built into frames with

openings 16 ft wide and 10 or 11 ft high, corre- sponding to the size of wall for those tested re- strained within the panel frame. For those

tested unrestrained or under load, the length was

decreased 2 to 3 in. by the clearance between the

wall and the frame, and similarly for the height of unrestrained walls. For walls tested under load,

the height was 10 ft 4 in. One wall, No. 10, was

built in two sections of 7-ft 9-in. and 7-ft 10-in. respective widths.

b. Small Walls

The frames into which the small walls were

built had openings 4 ft 2 in. wide and high.

As for the large walls, the clearance at the ends of walls tested under load reduced the width of the

wall by about 2 in.

4
Figuke 1. Design of walls.

.302992° —54 4
Figure 2. Design of 4-in. wall with pilasters.

3.3. Workmanship

a. Construction Methods

Almost all of the large walls were built by contract given to the lowest bidder, with the stipulation that only experienced masons be employed.

Observations were made on methods and rate of laying bricks, the degree to which joints were filled, and related construction details. From 1,000 to 3,300 bricks were required to lay the different walls, each wall requiring the time of one mason

from 1 to over 3 days, so that the ordinary work

routine might be expected.

Brick stretchers on side in solid walls were uniformly laid by the “spread-and-lay” method, the mason spreading mortar bed for 2 to 5 bricks at

a time. Mortar was generally applied to the

bricks on only one outside vertical edge before

being laid in place with little or no shoving.

Mortar was applied to headers near both ends of

the long side and sometimes for the greater part

of their length. The spread for the following course filled the transverse joints in both stretcher

and header course to some extent, and they were

found, on the average, three-fourths full on examination after test. The longitudinal joint between

stretcher courses in the 8-in. solid walls was found

from one-fourth to three-fourths full. In 12-in. solid walls, the longitudinal joints were more

nearly filled, the outside stretcher courses being

laid first and the center course laid in mortar

slushed in between the outside bricks. The

thickness of mortar joints was in the general range

of 0.40 to 0.60 in. For bricks set on edge in hollow rolok walls,

mortar was spread for the bed joint of several

bricks and applied to one vertical edge of stretchers

and near both ends on both sides of headers.

Somewhat more shoving and tapping of bricks for the rolok walls were necessary than for bricks laid

flat. The bed joints were found nearly uniformly f filled and vertical joints three-fourths full on the average.

b. Rate of Laying Bricks

The rate of laying bricks in the large walls built on contract varied from 625 to 1,960 bricks per mason per 8-hr day, depending upon the type and

thickness of wall, the skill and number of masons

working on a given wall, and the number and

efficiency of the helpers. The lower rates were

obtained with 1 mason and helper laying 4-in. walls and with 3 or 4 masons working on thicker

walls, the highest rates being for 1 mason and 2 helpers working on 8-in. solid walls. The average rate of laying for 8- and 12-in. hollow rolok walls was 910 bricks per mason per

8-hr day, the time required to construct walls of

equal area and thickness being nearly the same

as for solid walls. The rolok walls required from

25 to 30 percent less brick than solid walls of equal

area and thickness.

In table 4 the rate of laying bricks in the large

walls is given in terms of man-hours per 100 ft2 of

6
Table 4. Time required for construction of walls

Type of wall Design

(fig. No.)

Nominal

thick- ness Type of brick

Mortar: ce- ment, lime, and sand

(by volume)

Number

of walls

1-A

in.4 Surface clay or shale.. 1:154:6

1:154:6

1:154:8

1:0:3

5 Do f 2-

1 2-B

1-B

1 4

1. . _ do 1 Do

2 48

/

. ..do _ 7 Do.,.. 1-B 8 Surface clav. . 2 Do 1-B 8 do.. 0:154:3

1:154:6

1:1:8

2 A11 -rolok 1-D 8 Surface clay or shale 5 Cavity __ 1-F 10 Surface clay.. 3

Solid .... 1-B 8 Concrete or sand-lime 1:154:6 5 Do 1-C 12 Surface clav... 1:154:6 1:114:6 1:154:0

2 All-rolok ... 1-G 12 .•...do 1 Solid 1-C 12 Concrete or sand -lime. . 2

Average construction time

Masons Helpers

Man-hr/100

/' 2 6. 9 12.2

7.

7.3 8.0

7. 7 12. 1 9.4

10.9

11 . 1 14. 2

Man-hr/100

ft 2 9.3

17.6 8.3

7.8

10.1

8.9

5.4

10.3

9.4

13.8

12.7

Average

wall area

built per mason

ft Vhr

14.5 8.2

14.

13.7

12.5

13.0 8.3

10.8

9 2 9.0 7.0

1 Pilasters 4 by 4 in.. 1-ft 9 in. centers for one half of wall.

5 Pilasters 4 by 8 in.. 3-ft 9 in. centers for other half of wall.

wall and the average area of wall built per mason

per hour.

The comparatively low rate of laying bricks for

4-in. and cavity walls, considering the relative

number of bricks involved, is apparently due in large part to the greater care needed to keep the

newly laid masonry on line. The rate for the

4-in. walls with pilasters and for the hollow rolok

walls was also attributable to the masons’ lack of

experience in laying these types, as compared with

laying the usual 8- and 12-in. solid walls. As for

differences indicated in the table for type of brick

and mortar, the conditions were not uniform in point of number and skill of masons and helpers

working on given walls, for which due allowance

should be made in considering the nominally comparable figures. The averages also comprise fig- ures for five walls built by a mason in Government

employ.

Except for the 4-in. wall with pilasters, none of

the large walls were plastered. The face joints were struck and pointed, although not as uniformly as would be required on a commercial job.

In point of filling of interior joints and similar construction details, the workmanship was apparently

barely up to the average in commercial building

construction.

Five of the large walls and all of the small walls were built by masons in the employ of the Government, with the grade of workmanship probably a

little above the commercial average.

3.4. Auxiliary Strength Tests of Masonry

a. Test Specimens

At the time of building the walls for fire tests, an auxiliary masonry pier was built for almost all of the large walls and for a few of the small walls. These were 2 to 3 bricks long, or 16/2 to 25 in., the average height being near 2 ft 6 in. The

piers had aged 55 days or more at the time of test, and further seasoning probably would not have

materially increased their strength. They were

tested m compression, with results as summarized

in table 5, and the weight loss in seasoning up to the time of testing is also given.

The table further includes results of strength

tests of piers cut from walls after fire-endurance

or fire and hose-stream tests. For some of the

small walls, the whole test wall was subjected to the compression test after cooling, with some

regain in strength subsequent to the fire-endurance

test.

b. Strength of Solid Masonry

The average results indicate a strength for the

solid piers in the lower range of values, of four or more times the 160 lb/in. 2 working load applied to

8- and 12-in. walls tested under load in the fire- endurance tests. The strength with the portlandcement mortar was higher, and with the lime

mortar lower than for the cement-lime mortar,

with which most of the solid walls and all of the

hollow walls were laid. The average strength of masonry piers laid in lime mortar was 625 lb in. 2 In general, the strength of masonry increased

with the strength of the brick, although the rela- tion varied considerably as a result of other

properties, including the bond obtained with the

mortar. The high compressive strength developed

by the 4-in. walls is apparently attributable to the

absence of headers, the early breaking of which

in 8- and 12-in. walls contributed to failure at lower load.

c. Results with the Rolok Design

The strength for the rolok-type hollow wall with

bricks set on edge was lower than for solid walls,

being as an average only a little more than three

times the load of 160 lb in. 2 applied in the tire- endurance tests. However, according to buildingcocle requirements, the permitted working stress for hollow walls of brick is lower, being in the

range 80 to 125 lb/in. 2 of gross area.

/
Table 5. Compressive strength of brick piers

Brick Fire-test walls Mortar:

cement,

lime, and

sand (by volume)

Average

age Weight

loss in seasoning

Compressive strength Kind of piers Type and

source symbol

Compressive strength Wall Type

Design

(figure No.)

Nominal

thickness On side On edge

Iblin.z Ib/in.z in. Days Ib/ft. 3 lb/iv.2 CLM 3. 280 2. 560 1 Solid 1-A 4 1 :1\4:6 182 5 9 1 170 Do CLM 3.280 2. 560 11 __do l-B 8 1:134:6 146 4 5 850 Do CLM 3,280 2, 560 38 do 1-C 12 1:134:6 231 3 5 740 Do CLM 3,280 2. 560 54 All-rolok 1-D 8 1:134:6 135 3. 5 530 Do CLM 3.280 2, 560 64 do -- 1-G 12 1:134:6 232 4 9 630 Do CLM 3, 280 2, 560 14, 15 Solid. _ l-B 8 1:0:3 248 3 5 970 Do CLM 3. 130 1,960 16 __do l-B 8 0:134:3 126 2 5 510 Do CLM 3, 130 1,960 17 do l-B 8 0:134:3 409 6 7 720 Do CLM 3. 130 1,960 75 .do - l-B 8 1:134:6 224 0) 540 Do CLM 2, 960 2. 940 2 . . _do . 1-A 4 1 : 134:6 55 4 4 1 450 Do CLM 2, 960 2, 940 18 do - l-B 8 0:134:3 77 4.7 650 Do CLM 10 B 1-A 4 1:134:6 70 1 910 Do CLM 13 do l-B 8 1:114:6 97 (2) 630 Do CLM 40 1-C 12 1:134 *6 98 (2) 710 Do CLI 2, 920 2. 330 19. 21 do l-B 8 1:134:6 157 5 8 530 Do CLI 2. 920 2. 330 75 do l-B 8 l:lk:6 225 o) 400 no CLI 2, 920 2, 330 43 do 1-C 12 1:114:6 157 5.5 480 Do C LI 2. 920 2. 330 55 to 57 All-rolok 1-D 8 1:134:6 121 4. 4 450 SHW 8, 110 6, 400 5, 73 Solid 1-A 4 1:134:6 174 6 3 1 880 Do SHW 8. 110 6, 400 22, 23 _do’ l-B 8 1:134:6 89 5 8 1 530 Do SHW 8, 110 6, 400 58 All-rolok 1-D 8 1:134:6 316 4. 2 l’ 470 Do SHW 6, 450 5, 640 59 --. do 1-D 8 1 : 134:6 59 2 4 440 CON 2.780 1, 530 73 Solid. _- 1-A 4 1:134:6 238 8. 0 1 250 Do CON 2, 780 1,530 25 do l-B 8 1:134:6 72 4. 0 840 Do CON 2, 780 1, 530 26 l-B 8 1:134:6 314 5 3 870 Do CON 2. 780 1, 530 75 do . l-B 8 1:134:6 226 (i) 440 Do CON 2. 780 1, 530 45, 78 do. 1-C 12 1:134:6 161 6. 1 850 Do CON 2. 780 1,530 78 do 1-C 12 1:H4:6 174 0) 580 Do CON 2,780 1, 530 76 All-rolok 1-D 8 1 : 1J4:6 192 7. 4 440 Do COE 3, 350 2, 490 28 Solid l-B 8 1:H4:6 78 940 Do COE 3, 350 2, 490 28 ... _do l-B 8 1:134:6 78 « 430 Do COE 3. 350 2, 490 50 do 1-C 12 1:1J4:6 78 1 040

Sand-lime SLP 4, 630 4, 720 29,30 do l-B 8 lfU4:6 274 4.7 840 Do SLP 4. 630 4. 720 31 l-B 8 1:134:6 217 (2) 280 Do SLP 4, 630 4, 720 75 do l-B 8 1 : 1)4:6 228 0) 430 Do SLP 4, 630 4, 720 51, 78 do 1-C 12 1:1)4:6 219 6.0 890 Do SLD 2. 060 1,690 75 do l-B 8 1 : 1)4:6 221 7.0 830 Do SLD 2. 060 1,690 75 do l-B 8 1 : 1)4:6 224 (l) 390 Do SLD 2, 060 1,690 31 do l-B 8 1:1)4:6 215 (2

) 230 Do SLD 3, 050 2, 550 32 do . l-B 8 1 : 1)4:6 69 710 Do SLD 3,050 2, 550 32 do l-B 8 1: 1)4:6 81 ( 2

) 450 Do SLO 3. 600 3,000 36 do l-B 8 1:114:6 78 730 Do SLO 3,600 3, 000 36 do l-B 8 1 : 1)4:6 78 (

2

) 610 Do SLO 3,600 3,000 53 do 1-C 12 1 : 1 J4 :

78 810

1 Pier taken from wall after fire and hose-stream test.

3.5. Seasoning of Walls

a. Large Walls

The large walls were stored in the frames within

which they were boilt, with the base of wall about

4 ft above the floor of the building. The frames were suspended from trolley tracks and for the

seasoning period were placed 1^ to 4 ft apart in one end of the building. In cold or damp weather,

the drying of masonry was accelerated with three

warm-air furnaces, the storage space being segre- gated from the rest of the building with a canvas

curtain.

The age of the large walls at time of the fire- endurance test ranged from 28 to 100 days, in

general, the longer seasoning period being allowed

for the thicker walls. A measure of the degree of dryness at time of test was obtained by weighing

at intervals the companion piers built for compression tests. The fire test was not conducted

until there was no loss indicated in the weight of

2 Pier taken from wall after fire-endurance test.

the pier on successive weighings at intervals of a few days or until the loss was small. The piers were tested from 2 weeks to over 1 year after the

fire test of the companion wall, and the weighings

of the piers in the interval indicate the weight loss the walls subjected to the fire test might have had

on longer aging.

In general, the data indicate that although most

of the test walls had not reached constant weight

at the time of the fire test under the seasoning

conditions concerned, the further loss in weight for walls of clay and shale bricks would have been no more than 10 or 15 percent of the loss up to the

time of the fire test. However, if the seasoning

had extended into a period with more favorable

drying conditions, such as from the summer

through the winter months, the eventual loss in

weight would have been greater.

For the walls of concrete and sand-lime bricks,

the loss for more extended seasoning would apparently have been greater than for the walls of clay

8
and shale bricks. Although the rate of loss of the

piers immediately before the fire test of the walls was low, further seasoning of the piers for 5 or more months resulted in weight losses from 30 to 70 percent of those sustained before the time of the

fire test. The average weight loss of the piers at

the time of the compression test after aging an

average of about 230 days was 6.2 lb/ft,3 or between 4 and 5 percent of the weight of the

masonry. Hence, the indications are that if the concrete and sand-lime brick walls had been aged

as long as the piers they would have had a further

weight loss of 1 to 2 percent of their weight beyond

that obtained at the time of the fire test.

b. Small Walls

two 8-in. channels spanning the height of the frame

and bolted to webs of the top and bottom frame

members were placed one on each side of the

vertical center line of the panel.

The frames for the small walls were built of reinforced concrete or protected steel. For the frames

in which the walls were tested under load, the top

member was free from the side members and

served to transmit and distribute the load over the

wall. 4.2. Furnace Equipment

The furnace, a section of which is shown in figure 3, was used in fire tests of almost all of the

large walls. It was fired with fuel oil of specific

gravity 0.87 to 0.93, gas not being available at the

Figure 3. Section through

large testing furnace.

These walls were built in a building within which

ceramic furnaces were operated, with resulting

good drying conditions for the walls. Furthermore,

eight of the walls, after seasoning under room conditions f(?r about 1 month, were placed within enclosures and dried to constant or near constant- weight at average temperatures in the range 160°

to i80° F. On removal from the enclosure they

would gain in weight under room atmospheric

conditions.

4. Testing Equipment and Methods

4.1. Panel Frames

The large walls were built into frames constructed of 20-in. steel girder beams, the parts

thereof exposed to fire or heat as placed for the

fire t-est being protected with concrete. They were

supported on trolleys running on the lower flange

of overhead beams. The computed strength of the

frames as stressed by the expansion or loading of

the wall under test ranged from 340,000 to 400,000

lb. Although the highest load applied to the walls

did not exceed 240,000 lb, the loads induced by

expansion of the wall as exposed to fire might be

greater. To strengthen the frames into which the

heavier walls were built and to secure a greater

degree of restraint on the wall, members made of

CLAY SLAB DAMPLR5

scale:

FLOOR LINE

UJO

9
site. The oil was dispersed with jets of ah- at 20-

to 25- lb/m.2 pressure. Further air for combustion

and for forcing flame and heated ah- over the ex- posed side of the test wall was supplied by a blower

fan at the back of the burner chamber.

Originally, there were two main burners, which

later were increased to four. Four auxiliary

burners were also added, two on each side, one near

the midheight of the panel, and the other about

3 ft higher.

The last tests hi the series, Nos. 7, 70, 71, and 72, were made in a gas-fired furnace of design similar

to that shown hi figure 3, descriptions of which are given in BMS71, BMS117, and BMS120 [2, 3, 4], The tests of the small walls were conducted in a gas-fired furnace having four blast burners on each

side projecting flame at a small angle on the back

wall of tlie chamber, which curved outward toward

the center of the test wall. Auxiliary inlets on each

side supplied the additional compressed air re- quired for combustion. A view of this furnace is given in figure 9 of RP37 [1],

4.3. Loading and Restraint

The large walls tested under working load were supported on two heavy channels about 8 ft long,

under each of which were placed two 200-ton

hydraulic jacks resting on the lower member of

the panel frame. The jacks were actuated by oil under pressure from a motor-driven pump. The

oil pressures, which seldom exceeded 1,000 lb/in.2

, were measured with gages and a fluid-pressure

scale. Load on the small walls was applied with

a hydraulic jack bearing against an overhead

member secured at its ends to the bottom member

of the panel frame.

The walls tested restrained were built solidly

into the panel frames. The restraint was relieved

to the extent that the panel frame members deflected under pressure from the expanding wall

and also from the deflection of the members due

to uneven heating. The measurements made on

the frames for the large walls indicated that at the

midpoint the top member deflected upward during

test in the range % to 1 in., and the bottom member deflected similarly downward. The side

members deflected inward by smaller amounts

2-9"

j where there was clearance between them and the . test wall. The greater part of these deflections was apparently due to temperature effects on the I panel members.

A number of the large 8- or 12-in. -thick walls

' were built clear of the panel frame at the top and

sides, thus allowing them to deflect freely because | of the temperature difference between their fire- I exposed and unexposed sides. To prevent undue

curvature at the top of the 8-in. walls, an 8- by

8-in. pilaster was built into them at each end on

the unexposed side.

4.4. Furnace Fire Exposure

a. Furnace Control Curve

At the time these fire stests were begun, the !j control of furnace temperatures had been standardized to call for an average of 1,550° F (843° C)

at the end of % hr, 1,700° F (927° C) at 1 hr, and

1,850° F (1,010° C) at 1 % hr. Subsequent to this,

j the rise was constant at 75 deg F per hour, the

temperature for the 4-hr point being 2,000° F

(1,093° C), and 2,300° F (1,260° C) at 8 hr. In the tests carried beyond 8 hr, it was the in- , tention to continue raising the furnace temperature 75 deg F per hour until 2,500° F was reached ( at 10 hr 40 min, after which it was to be maintained

at this level. According to a later revision of the

standard, the temperature of 2,300° F at 8 hr is to be maintained for longer test durations. These

furnace reference curves are shown in dashed lines on the time-temperature plots.

b. Pyrometer Mounting

The furnace pyrometer mounting initially used

is shown in figure 4, the thermocouple wires being

in pairs of chromel and alumel. On account of

f the high cost and frequent breakage with this type of mounting, %-m. black-iron pipes were

J later substituted, capped or welded closed at the

furnace end. Thermoelectric properties of chromel-alumel wire are not affected by black

iron even at the temperature of the furnace, and

it was also found that the lag and radiation effects on the temperature readings are about the same

as for the procelain-tube mounting.

•r-3-

Figure 4. Detail of furnace pyrometer mounting.

10
In the tests with the furnace shown in figure 3,

there were six furnace pyrometers thus mounted,

symmetrically placed 3 ft above and below the

center line of the panel, two on the vertical center

line, and two 5% ft from it on each side. The

end of the mounting was kept at approximately

3 in. from the wall under test. In the tests conducted in the small furnace, six pyrometers with iron-pipe mountings were located

in two vertical rows 1 ft to the side of the center

of the panel, with two on the horizontal center

line, two 14 in. above and two below it, similarly

placed.

c. Lag and Radiation Effects Because of the insulating effect of the mounting [5], the thermocouple readings during the

initial part of the test were far below the temperature of the furnace gases, and even at 5 min

the lag was in the order of 150 to 250 deg F. However, at 20 to 30 min, the lag effect was not

appreciable.

The mounting was also cooled by radiation from

furnace and test walls that were at lower temperatures than the furnace gases. During the first part of the test, this may affect the readings by

as much as 300 deg F, decreasing, as the furnace

and test walls heat up, to the order of 100 deg F

at 4 or 5 hr. The temperatures called for according to the

furnace control curve are adjusted to allow for the lag and radiation effects that were incurred

with the prescribed pyrometer mounting.

d. Unprotected Furnace Thermocouples

To obtain information on the temperature variation in the large furnace and some indications of lag and radiation effects on the readings of the

mounted furnace thermocouples, nine unprotected

thermocouples of No. 18 B&S gage chromelalumel wire were placed with a 12-in. length in the furnace and the thermocouple junction about

1 in. from the fire-exposed face of the wall. They

were located symmetrically with reference to the

center of the panel, 3 on the horizontal center

line and 3 distant 1% ft from its top, bottom, or

side borders.

4.5.

Determination of Wall Temperatures

Temperatures at the center of the thickness of 4- and 8-in. walls and between the wythes of

12-in. walls were determined with 5 chromelalumel thermocouples, the leads for 6 in. or more

from the junction being placed parallel with the

wall. The temperatures of the unexposed face of the

wall were obtained with iron-constantan or chromel-alumel thermocouples, the wire size ranging from No. 22 to No. 30 B&S gage. The

regular number for the large walls was 13, of

which 9 were located over the central one-third

of the area. They were in close contact with tin- wall surface and freely exposed. Other thermocouples were placed over holes or cracks that

developed as the test progressed. In addition,

1 or 2 thermocouples on the face of the lower

part of the wall were covered with 3 / in. of loose cotton in a 3-ft square box or were in contact with the board face of a similar box filled with

wood excelsior. This simulated conditions where

clothing or bales or crates of combustible materials

are in contact with the unexposed side. After a number of the tests had been completed,

the method of temperat ure measurement on the

unexposed surface was standardized to require

thermocouples or thermometers under asbestos

pads 6 in. sq and 0.40 in. thick. [6] For some

time prior and subsequent thereto, the determinations were thus made, although parallel determinations were made with uncovered thermocouples

to obtain approximate correlation of readings.

The temperatures on the unexposed face of the

small walls were determined with uncovered

thermocouples and with thermocouples or thermometers under the 0.40-in. -thick asbestos pads,

generally 3 in number, located 1 at the center of

the wall and the others about 1 ft distant on a diagonal center line.

4.6.

Calibration of Thermocouples

The temperature-emf relations of representative

samples of the thermocouple wire were determined

by comparison with a thermocouple for which

this relation was known. Due to changed temperature-emf relations on reheating after use at high temperatures, the furnace thermocouples were replaced for each test except for those of short duration. Thermocouples in the walls were

also thus replaced if the temperatures indicated

had been above certain limits.

4.7.

Deflection Measurements

The deflections of the large walls were measured

with reference to weighted wires suspended from

the top member of the panel frame and passed

through holes in pegs secured to the lower member.

Measurements were made at the center of the

wall and at the quarter points of the height and

width. For the walls tested unrestrained, deflec- tions were also measured at the top center and

top corners and at two intermediate points.

4.8.

Hose-Stream Tests

Typical wall constructions were subjected to hose-stream tests after fire exposures of given

durations. The tests were conducted according

to the ASTM or ASA fire-test standard applicable

at the tune. The stream was delivered through a National Standard playpipe having IVin. nozzle

diameter, the water pressure being obtained with

a motor-driven centrifugal pump.

11
sides and top of the frame.

Most of the walls were laid in mortar having

1 : 1 >4 : 6 or 1:1%: 6, volume parts of portland

cement, hydrated lime, and sand. These are equivalent, respectively, to about 1:0.53:5 and ! 1:0.64:5 parts by weight of dry materials. Two

of the walls were laid up in portland cement and

| mortar, proportioned 1:3 by volume, and three

in lime mortar proportioned 1%:3 by volume.

All but six were tested without plaster finish on

either side.

Table 6. Description of solid brick walls for fire-endurance tests

Wall dimensions Brick Mortar :ce- Plaster Design ment, Restraint or Age at Wall or

test

(fig- Type and

source symbol

lime, and loading during time of Nominal

thickness Length Height No.) Kind Locality sand (by volume)

Fire-exposed

side Unexposedside

test test

in. ft in. ft in. Days

1

1 4 16 0 11 0 1-A Clay__ Md CLM 1:1M:6

1:1M:6

1:1J4:6

l:l/4:6

1:114:6

1:114:6

1:114:6 1:114:6

1:114:6 1:114:6

None 69 { 2 4 15 6 10 4 1-A ...do . Md CLM ...do . 80 lb/in.2 .. 43 3 4 4 2 4 2 1-A ...do _ Md CLM ...do . 50

i

4 4 4 2 4 2 1-A ...do . Md CLM ..do. .. 38 1 5 4 16 0 11 0 1-A Shale .. . West Va_. SHW 37

6 4 15 9 10 4 1-A _ .do... ._ West Va.. SHW do ...do 80 lb/in.2 39

1

j 7 4 16 0 10 0 1-A Clay N. Y CLN 29

8 4 4 2 4 2 1-A .. do Md CLM Cement Cement. ...do 40

1

9 4 4 2 4 2 1-A _. .do Md CLM Gypsum.

None

41 10A 4 7 10 10 4 2-A Shale West Va.. SHW (Lime on

1 wood lath. 160 lb/in.2 /

' 50

l

2 35

1

10B 4 7 9 10 4 2-B Clay. Md CLM 1:114:6

/14-in. ce- 160 lb/in. 2 /

1 53

l

2 38

1 1 ment.

11 8 16 0 11 0 1-B ...do Md CLM 1:114:6 1:114:6

46 j 12 8 4 2 4 2 1-B ...do Md CLM do ...do do 75

13 8 4 2 4 2 1-B ...do Md CLM 1:114:6 do ...do do 3 D

14 8 15 10 10 10 1-B ...do Md CLM 1:0:3 ...do 34

15 8 16 0 11 0 1-B . . .do Md CLM 1:0:3 ...do 77

16 8 15 10 10 10 1-B Md... CLM 0:114:3

0:114:3 0:114:3

1:114:6

35

17 8 16 0 11 0 1-B ..do Md CLM ...do 34

18 8 15 9 10 4 1-B Md CLM .do ... 120 lb/in. 2 50

19 8 15 10 10 ii 1-B ...do 111 CLI do --.do Partly re- 65

strained. 20 8 16 0 11 0 1-B 111 CLI 1:114:6

1:114:6

57

21 8 16 0 11 0 1-B ...do 111 CLI do ...do do 52 22 8 16 0 11 0 1-B Shale West Va.. SHW 1:114:6

1:114:6 do. . . .do _ do.. 35

23 8 15 10 10 10 1-B ...do West Va__ SHW do __.do Unrestrained.. 43 1 24 8 4 2 4 2 1-B ...do West Va_. SHW 1:114:6 do --.do Restrained 56 1 25 8 15 10 10 10 1-B Concrete.. N. Y CON 1:114:6 do -.-do Unrestrained.. 32

! 26 8 16 0 11 0 1-B . do . N. Y CON 1:114:6

1:114:6 __.do 34 ! 27 8 4 2 4 2 1-B ...do D. C COD do .. -..do do 80 i

28 8 4 0 4 2 1-B .do D. C COE 1:114:6 1:114:6 do ...do 160 lb/in. 2 ... 3 D i 29 8 16 0 11 0 1-B Sand-lime. Pa SLP do ..-do Restrained 40

30 8 15 10 10 10 1-B ...do Pa SLP 1:114:6 do .--do Unrestrained.. 42

31 . 8 15 10 10 10 1-B ...do /Pa

\D. C SLP SLD } 1:114:6 do ...do.. do 35

32 8 15 9 10 4 1-B ...do D. C SLD 1:114:6 do ...do 146 lb/in.2 63 33 8 4 2 4 2 1-B ...do D. C SLD 1:114:6

1:114:6 do. ..do Restrained ._ 34 8 4 0 4 2 1-B ...do D. C SLD do ...do 160 lb/in.2 46 35 8 4 0 4 2 1-B ...do D. C SLD 1:114:6 do __.do 160 lb/in.2 3 D

36 8 4 0 4 2 1-B ...do Ohio SLO 1:114:6 do ...do 160 lb/in. 2 3 D

37 8 4 2 4 2 1-B Clay Md CLM 1:114 = 6 Gvpsum . . Gypsum _ Restrained 47 38 12 15 10 10 10 1-0 ...do . Md. CLM 1:114:6 1:114:6

83

39 12 4 2 4 2 1-C ...do Md CLM do ...do Restrained 48 40 12 4 0 4 2 1-C ...do Md CLM 1:114:6 do ...do 160 lb/in.2 2 D

41 12 4 2 4 2 1-C ...do Md CLM 1:114:6 do ...do Restrained 44 42 12 4 2 4 2 1-C _do_._ _. Md CLM 1:114:6

1:114:6

Lime do /

1 41 l

2 22

54

•’;!

43 12 16 0 11 0 1-C ...do Ill CLI None ...do do

44 12 4 0 4 2 1-C ...do 111 CLI 1:114:6 do ... ...do 160 lb/in. 2 82

45 12 4 0 4 2 1-C Shale West Va.. SHW 1:114:6 do -_-do 160 lb/in.2 77

i 46 12 16 0 11 0 1-C Concrete . N. Y CON 1:114:6 1:114:6

1:114:6

1:114:6

do __do Restrained... 38

47 12 4 0 4 2 1-C ...do D. C COD . .do do 160 lb/in.2

. 82

48 12 4 2 4 2 1-C ...do . D. C COD 53 si 49 12 4 0 4 2 1-C ...do D. C COD do ...do 160 lb/in.2 3 D

50 12 4 0 4 2 1-C ...do D. C COE 1:114:6 do ...do 160 lb/in.2 3 D -

1, 51 12 16 0 11 0 1-C Sand-lime. Pa SLP 1:114:6 do .. ...do Restrained 48

52 12 4 0 4 2 1-C ...do D. C SLD 1:114:6 do ...do 160 lb/in.2 78 53 12 4 0 4 2 1-C ...do Ohio SLO 1:114:6 do ...do 160 lb/in.2 3 D

1 Masonry. 2 Plaster. 3 Dried to constant weight.. 12

5. Program of Tests

5.1. Solid Walls

Table 6 gives the schedule of fire-endurance

tests of solid brick walls, the designs of which

are shown in figure 1 (A to C) and in figure 2. The schedule included 27 tests of large walls and

about an equal number of the smaller size. They

were tested either under working load, restrained

within the panel frame, or in the unrestrained

condition with a clearance of % to 1% in. from the

i
5.2. Walls of Hollow Design 5.3. Fire and Hose- Stream Tests

Table 7 gives the schedule of fire-endurance

I tests of walls having one or more cavities spanned

by header bricks or wire ties, the designs of which

are given in figure 1 (D to L). They were all of clay or shale bricks laid up in portland-cementlime-sand mortar. The conditions of loading and

restraint were the same as for the solid walls.

Table 8 describes the walls which were subjected

to a hose-stream test after a fire-exposure of 1 hr

or after the fire-endurance test. Most of them

were built in three or more sections bonded to- gether and of bricks representative of those in the walls for the fire-endurance tests.

Table 7. Description of hollow walls for fire-endurance tests

Wall

1 or

! test

:

Wall dimensions Wall design Brick Mortar:

cement,

lime, and

sand (by volume)

Plaster Restraint

or loading during test

Age at time j of test Nominal

thick- ness Length Height Type Figure No. Kind Locality Type and

source symbol

Fire- exposed

side

Unexposed

side

54

in.8

ft15

in. 10

ft10

in. 10 All-rolok__ 1-D Clay__ Md CLM 1:134:6 None None Unrestrained. Days

40

55 8 15 10 10 10 do 1-D ---do... 111 CLI 1:134:6 -_.do ...do do 34 56 8 16 0 11 0 do 1-D ---do... 111 CLI 1:134:6 ...do ...do Restrained . .

38

57 8 16 0 11 0 do 1-D .--do... 111 CLI 1:134:6 . ..do ...do do 40

58 8 15 10 10 10 do 1-D Shale _ W. Va... SHW 1:134:6 ...do ...do Unrestrained. 53

59 8 15 9 10 4 do 1-D __-do.-- W. Va... SHW 1:134:6 ...do ...do 160 lb/in.2 32'

60 8 4 2 4 2 do 1-D Clay.. Md CLM 1:134:6 Lime Lime Restrained... /

1 42

\

2 28

61 8 4 2 4 2 do 1-D ...do.-- Md CLM 1:134:6 Gvpsum _ Gypsum

do 45

62 8 4 0 4 2 Rolok-bak. 1-E . _do_-_ Md.. CLM 1:134:6

1:134:6 ...do None 160 lh/in.2 160 lb/in.2 43

63 8 4 0 4 2 do 1-E ...do-.. Md CLM Lime ...do 46

64 12 15 10 10 10 All-rolok. 1-F _-_do.__ Md CLM 1:134:6 None ...do Unrestrained. 100 65 12 4 2 4 2 Alt. rolok _ 1-G -_.do._- Md CLM 1:134:6 ...do ...do Restrained. __ 47

66 12 4 2 4 2 do 1-G ...do... Md CLM 1:134:6 Gypsum. Gypsum

do /

1 46

\

2 31 67 12 4 2 4 2 Flat-bond 1-H .-.do... Md CLM 1:134:6 ...do ...do do 46

68 12 4 0 4 2

rolok. Rolok-bak. 1-J .-do... Md CLM 1:134:6

1:134:6

None None Unrestrained. 41

69 12 4 0 4 2 Rolok- 1-K _ -_do._- Md CLM ...do ...do 160 lb/in.2 41

70 10 15 9 10 4 faced. Cavity 1-L _-.do.__ N. Y CLN 1:1:6 ...do ...do 125 lb/in.2 48

71 10 15 10 10 4 do 1-L ...do... N. Y CLN 1:1:6 ...do ...do 54 lb/in.2 33

72

i

10 16 0 10 0 do 1-L __.do._- N. Y CLN 1:1:6 -..do: ...do Restrained. _. 41

1 Masonry. 2 Plaster. Table 8. Description of walls for fire and hose-stream tests No plaster was applied on any of the walls subjected to the fire and hose stream test

Size of wall Wall design Number

of sec- tions

Brick symbol

for respective sec- tions

Mortar: cement,

lime, and sand

(by volume)

1

Age at time of

test

Wall or

test Nominal

thick- ness Length Height Type Figure No.

Restraint or loading during test

73

in.

4

ft in.

16 0

ft in.

11 0 Solid . 1-A 8

f CLM

CLI

\ SHW Restrained

Days

36

71 4 16 0 10 0 do 1-A 1 CON

[ SLP CLN

j

1:134:6

1:134:6 do 29

74 8 15 10 10 10 do 1-B 8 CLM

CLI SHW 1:134:6 Unrestrained. 34

75 8 16 0 11 0 do 1-B 8

CON

SLP CLM

CLI SHW

CON

1

l:134:6 Restrained . 26

76

77

8 16 0

15 10

11 0 1-D 8

SLP SLD

CLM

CLI SHW jl:134:6

1:134:6 one half:

.do 26

8 10 10 do 1-D. 10 28 CON

. SLP

do 3 Unrestrained

78A 12 15 10 11 0 Solid 1-C 3

| CON

{ SLP

1 : 3i o:6 one half,

ll :134:6. Restrained 45 78B 2 12 15 10 10 10 1-C . 3

1

l SLD

do 4

1 1:134:6 ... Unrestrained 56

71 i 10 15 10 10 4 1-L CLN 1:1:6 54 lb in 3 33

72 ‘ 10 16 0 10 0 do 1-L 1 CLN 1:1:6 Restrained 41

1 Hose stream applied at the end of the fire-endurance test. 2 Test No. 78!) was made with the same wall as Test No. 7SA but t i' b' k c ursc h , . N

moved so wall could be tested in the unrestrained condition. Mortar joints washed out in the previous hose-stream test had been repointed.

3 Includes CLM, CLI, SHW, CON, SLP. « Includes CON, SLP, SLD.

302992° —54 3
6. Results of Fire- Endurance Tests

6.1. Criteria of Fire-Endurance Limit

The results of the fire-endurance tests from the

standpoint of limits of temperature rise on the

unexposed surface and within the wall are given

in the tables in sections 6.2 and 6.3. Also given

is the time at which some of the walls exposed

to fire under load failed under the working load

applied, this being their fire-endurance limit in the

absence of a lower limit based upon other criteria.

a. Limits of Surface-Temperature Rise

According to the test specifications cited [6] and later issues thereof, the permissible average

limit of temperature rise on the unexposed surface

above the initial is 250 deg F, and for a single location, 325 deg F. This assumes that measurements

are made under the prescribed asbestos pads. As

previously indicated, in the earlier tests the

greater number of temperature measurements

were made on the freely exposed surface. A

comparison of results where both methods were

used indicate that the average limit of temperature rise under the asbestos pads is reached in about 0.84 of the time the limit is reached with the

uncovered thermocouples. This agrees closely

with results of similar comparisons reported and

applied in a previous paper [1], Accordingly, in the tables in sections 6.2 and 6.3, for tests where

the average limit of surface temperature rise was

obtained only on the free- surface, the derived

limit for determination under the asbestos pads,

obtained by applying the above factor, is given

in italics. It appears that results thus derived come well within the limits of variation due to difference in materials and bricks within groups

for which the results are herein summarized in terms of average values.

Significant information is also obtained from

the time limits of temperature rise obtained under

the large cotton pad and excelsior box applied on the unexposed surface in the earlier tests and

also the limits indicated over cracks and imperfect

joints.

b. Temperature Rise Within the Wall

The limits of temperature rise within the wall are given in the last double column of the tables

in section 6.2 and 6.3. These are used as the

basis for indicating fire-endurance limits of walls

having combustible members framed into them

for a 4-in. depth from the unexposed side.

c. Residual Temperature Rise

Where the limit of temperature rise was reached

after the fire was shut off, it is included in parenthesis in the tables, except where the lag is only

a few minutes. Although not applied as a basis

for fire-endurance limits, it is significant as indi- cating the degree of temperature rise after the

end of the fire exposure, with the wall remaining in

front of the furnace in the same position as during

the test.

d. Lateral Deflection Although the test specifications do not place a

limit on lateral deflections, they determine to a

large extent the ability to sustain load and the

stability under fire exposure. Lateral deflections are largely due to temperature differences between

the fire-exposed and unexposed surfaces of the

wall. The center deflection, f, for the restrained or loaded wall, free from the panel frame at the

sides, can be expressed approximately by the fol- lowing relation: [7]

/

Ch2(T2 —Ti)

rTi >

where C is a constant involving the coefficient of expansion of the wall material, h is height, t the

wall thickness, and (T2-T] ) the temperature differ- ence between the fire-exposed and unexposed sides

of the wall. Based upon the same considerations, the deflec- tion at the top of unrestrained walls will be four

times the center deflection for the restrained or loaded condition.

6.2. Results With Solid-Wall Constructions

The solid-wall constructions in 4-, 8-, or 12-in. nominal thickness, for which results are given in table 9, were built of clay, shale, concrete, or I sand-lime bricks.

a. Walls of 4-in. Thickness

The 4-in. walls were all of clay and shale bricks

and were tested either under load or restrained

within the panel frame. There was no failure under load or from excessive deflection before the

time corresponding to their fire-endurance limit as determined by temperature rise on the unexposed

surface.

( 1 ) Temperature-rise limits. The temperature

rise of 250 deg F was reached in an average time of

1 hr 21 min for the unplastered walls as referenced

to temperatures under the asbestos pads. A

%-in. thickness of portland cement or gypsum

plaster on both side (tests 8 and 9) increased the

fire-endurance by 1 to 1 / hr. One wall tested in two sections, 10A and 10B, was stiffened with pilasters (fig. 2). Lime plaster on wood lath was applied over the pilasters on the

fire-exposed side of 10A and a %-in. thickness of portland-cement plaster on the unexposed side of 10B. Although the pilasters decreased the maximum center deflections to % in., the plaster finish added little to the fire-endurance periods.

(2) Time-te?nperature curves. The temperature

curves for tests of 4-in. walls are given in figures

5, 6, and 7. The curves marked F give the temperatures indicated by the furnace pyrometers

14
mounted as shown in figure 4. For test 5, the

curves marked 1 give the average, maximum, and

minimum temperatures indicated by 9 unprotected furnace thermocouples of Xo. 18 gage wires

placed with junctions about 1 in. from the fire- exposed face of the wall. The curves marked P give the temperatures

under the standard 6- by 6- by 0.4-in. asbestos

pads placed against the unexposed face of the wall,

and those marked S, the temperatures indicated

by thermocouples in close contact with the unex- posed face but freely exposed. Other curves give

temperatures under the 3- by 3-ft pads or boxes

filled with cotton or excelsior applied to the unexposed side of the walls in some of the earlier tests and shown in place in figure 8. The arrows on the curves of temperature on the

unexposecl side indicate the time when an average

temperature rise limit of 250 deg F, or a rise at any thermocouple location of 325 deg F, is reached,

whichever in any given test occurs earlier.

(3) Lateral deflections. Typical deflection curves

for tests of 4-in. walls are given in figure 9. For

walls made of bricks from the same source, the

deflections of those tested restrained were greater

than for tests under load, the highest deflection

being obtained with a restrained shale-brick wall. Figure 10 shows the unexposed side of a 4-in. clay-brick wall after a fire-endurance test of 1 hr

25 min, followed by hose-stream application on

the fire-exposed side. The maximum deflection of

6 in. during the fire exposure was decreased to no more than 3 in. from the cooling effect of the hose

stream.

b. Clay- and Shale-Brick Walls of 8-in. Thickness

The details of construction and main results of

tests for solid 8-in. walls built of clay or shale

bricks in the group 11 to 24 and plastered wall

37 are given in tables 6 and 9. Wall 18, laid up

in lime mortar, was tested under load, the rest being tested restrained within the panel frame or

built free from the frame at sides and top for test in the unrestrained condition.

( 1 ) Surface-temperature limits. Most of the

present tests are within the group of large walls

in which the fire exposure was limited to 6 hr, on

the ground that in regulations such as building

codes no higher fire resistance is required. In fact,

the maximum required does not generally exceed

4 hr. With the 6-hr test limit and temperatures on

the unexposed side determined on the free surface,

the limit of 250 deg average rise was attained only

in test 19. However, significant information was

obtained from the times at which the temperaturerise limits occurred under the large cotton pad,

excelsior box, and at cracks (see fig. 11). Also,

in test No. 12 (fig. 12) the rise limit was determined with thermometers under the standard

asbestos pads.

Based on the results of these determinations

and with allowance for the methods used, the

average fire-endurance limit of 8-in. walls built

of clay or shale bricks and normally seasoned, was indicated as being near 5 hr. With gypsurri

plaster on both sides (test 37), the limit of surface

temperature rise was not reached until after 9 hr. Although the increment in fire endurance due to

plaster increases with wall thickness, in this case, the plastered wall apparently had not attained

the degree of dryness of unplastered w

r alls at the

time of testing. The lag in temperature rise is shown by the temperature curves in figure 13.

(2) Wall-temperature limits. The permissible

temperature rise within the wall, 4 in. from the

unexposed surface, was reached in an average

time of 2 hr 16 min for the 12 normally seasoned

walls. The average of the six lowest result- was 2 hr.

(3) Effect of drying at elevated temperature*

Wall 13 was dried to constant weight at temperatures in the range 160° to 180° F. The 325-deg-F

average temperature rise was reached in the

wall 4 in. from the unexposed surface at 2 hr 1 min

and an average rise of 250 deg F on the unexposed

surface under the asbestos pads at 4 hr 9 min.

The latter compares with 5 hr 11 min for the

companion wall 12, aged under room conditions.

Because wall 13 gained in weight under dry

heated-room conditions after removal from the

drying chamber, it was apparently in a drier

condition than walls would usually be after ex- tended aging in heated buildings.

(f) Loading, restraint, and lateral deflection. Wall 18, laid up in lime mortar, was tested under

load of 120 lb/in. 2

, which was sustained throughout

a fire test terminated at 6 hr. The original

compressive strength of the masonry was 650

lb/in. 2 The maximum lateral deflection was about

1 in. (fig. 9). No further fire tests under load were made of 8-in. solid walls of clay or shale

bricks because it was apparent that the load

would be sustained.

For walls of brick from the same source (CLM

as the loaded wall and tested restrained within

the panel frame, No. 17 laid up in lime mortar

deflected about 1 in. and walls 11 and 15, laid up

in cement-lime or cement mortar, near 2 in. The maximum deflection of walls of clay bricks

from the other source, CLI, (tests 19, 20, 21 and of shale bricks, SHW (test 22) and tested

restrained, were in the range 2 b to 4 in. (tig. 9 . The maximum deflection at the top of the walltested unrestrained (Nos. 14, 16, and 23, fig. 9 was on the average a little less than four times

the center deflection for comparable restrained or loaded walls, which is in fair agreement with the

relation derived from theory [7], There was no collapse from excessive deflection

of restrained or unrestrained 8-in. walls of clay

and shale bricks as tested on 1 1 -ft height for 6 hr. which is beyond their lire endurance as limited by

15
Table 9. Results of fire-endurance tests of solid walls of clay, shale, concrete, or sand-lime bricks

Walls having minimum lateral dimensions of 10 ft and area of 100 ft 2 conform to present requirements of ASTM Standard E119

Wall

or test Nominalthickness Wall

area Brick symbol

Plaster

Restraint or load- ing during test

Age at time

of test

Test duration

Severity

of furnace exposure

Fire-exposed LTnexposed Time Why ended

in. u

2

Days hr min Percent

1 4 176 CLM Restrained 69 6 1 98 7 2 4 160 CLM 80 lb/in.2 43 2 20 100 4

3 4 17.4 CLM _ ___do do ... Restrained 50 1 10 do _ 100.

4 4 17. 4 CLM do 38 0 45 98. 0

5 4 176 SHW do 37 2 41 99. 8

6 4 163 SHW 80 lb/in. 2

. 39 1 44 100. 6

7 4 160 CLN Restrained 29 1 25 100. 5 8 4 17. 4 CLM do 40 4 9 98. 8

9 4 17. 4 CLM do 41 4 1 98. 7 10A i 4 81 SHW 160 lb/in.2 50 2 30 do . 101. 7 10B 2 4 80 CLM ...do 53 9 30 ... .do 101. 7

11 8 176 CLM Restrained 46 6 1 Set limit 99. 5 12 8 17. 4 CLM do 75 5 10 High wall temp 98. 8 13 8 17. 4 CLM do. D 3 4 09 99. 4 14 8 171 CLM __ do do Unrestrained 34 6 01 Set limit 97.5

15 8 176 CLM ...do - . . do Restrained. 77 6 03 do -- 99.

16 8 171 CLM Unrestrained 35 6 1 ... .do 99.0

17 8 176 CLM Restrained 34 6 0 do - 100.2

18 8 163 CLM . do _ .. - 160 lb/in. 2 50 6 0 do . --. 98.3

19 8 173 CLI _ do Partly restrained . 65 6 2 do --. - 100. 5 20 8 176 CLI _ do .. -- Restrained 57 6 1 ... .do -.- -- 99.3

21 8 176 CLI ._ do 52 6 2 do - 97.5 22 8 176 SHW _ _ do.. 35 6 1 do ... 99.6

23 8 171 SHW Unrestrained 43 6 1 do ... . 100.8

24 8 17.4 SHW Restrained 56 4 0 do 98. 8 25 8 171 CON Unrestrained.- -- 32 6 1 do 100. 2

26 8 176 CON 34 6 2 99.0

27 8 17.4 COD ..do do 80 7 0 Hisrh wall temp 98. 7 28 8 16. 7 COE 160 lb/in. 2 . ... D 3 6 17 do 99. 8 29 8 176 SLP 40 6 1 Set limit 99. 1 30 8 171 SLP 42 6 1 do ... 100.8

31

' 8 171 /SLP

J ...do do 35 6 1 do 99.9

32 8 163

IfeLT) SLD 146 lb/in. 2 63 6 0 do... 98.2

33 8 17.4 SLD Restrained 77 10 6 High wall temp. ... 98. 3

• 34 8 16.7 SLD do... 160 lb/in.2 46 8 0 Set limit .. 97.4

35 8 16.7 SLD ._ do .... . .. do D 3 7 45 High wall temp 98.2

36 8 16.7 SLO do ...do do ... D 3 6 41 do 100.8

37 8 17.4 CLM 47 11 2 do.. . 100.2 38 12 171 CLM None . Unrestrained _ 83 5 51 Equip, failure 98.9

39 12 17.4 CLM do -- .. do Restrained __ 48 11 36 Set limit .. .. 101.6

40 12 16.7 CLM do do 160 lb/in.2 . D 3 10 22 High wall temp 98.5

41 12 17.4 CLM .. _ do 44 8 0 Set limit 98.9 42 12 17.4 CLM Lime __ do 41 16 5 High wall temp . _ 105.2 43 12 176 CLI None do . _ _ do 54 6 0 Set limit 98.0

44 12 16.7 CLI do . . 160 lb/in. 2 82 10 21 100.

45 12 16.7 SHW do do . 77 12 50 High wall temp 101.3

46 12 176 CON do 38 6 1 98.8

47 12 16.7 COD . .. do . - 160 lb/in.2 82 16 4 High wall temp 102.8

48 12 17.4 COD do _ __ 53 12 30 Set limit 100.6

49 12 16. 7 COD do . _ do 160 lb/in.2 ,.. D 3 13 55 High wall temp. . .. 99.4

50 12 16.7 COE do .. do D 3 14 0 do 101.3

51 12 176 SLP _. __do 48 6 1 98.5

52 12 16.7 SLD do 160 lb/in.2 78 9 57 99. 7 53 12 16.7 SLO . ...do D 3 13 53 101.0

1 With pilasters. See figure 2, A.

2 With pilasters. See figure 2, B.

3 Dried to constant weight at temperatuies of 160° to 180° F.

temperature rise on the unexposed side. The

unrestrained walls, all with 8- by 8-in. pilasters

at the ends, deflected outward at the top up to

8 in., the pilasters serving to keep the top in approximate straight alinement (fig. 14).

(5) Effect of cracks and imperfect joints. The

large walls were nearly all laid up by contract,

and the workmanship as a whole was barely up

to good construction practice. The filling and

pointing of mortar joints on the surface of unplastered walls apparently was not as well done

as would be required on a construction job.

Accordingly, steam and hot gases issued through

small holes in the imperfect joints with temperatures over them higher than those on the

adjacent surface. Such higher temperatures also occurred over

cracks formed during test. These cracks varied

from very fine to those with openings of % to Ze in. The larger openings were generally at

16
Table 9. Results of fire-endurance tests of solid walls of clay, shale, concrete, or sand-lime bricks—Continued

Wall or

test

Temperature rise at unexposed surface Time of temp rature

rise in wall 4 in. from Average at end of test Time of average 250 deg F rise Time of 325 deg F rise at one location unexposed surface

Asbestos pad Free surface Asbestos pad Free surface Cotton pad Excelsior box

Asbestos pad Free surface* Over crack

325 deg. F

average

422 deg. F maximum

° F

o F hr min hr min hr min hr min hr min hr min hr min hr min hr min

1 < 1 37 1 56 1 41 2 3 2 419 1 20 1 35 1 11 1 25 1 39 1 28

3 260 ?19 1 8 (1 17) 5 (1 19) (1 27) 4 113 117 (1 12) nr (1 39) 5 468 1 19 1 34 1 19 1 35 1 36

6 206 nr 1 30 1 36 1 30

7 269 1 22 1 21 8 453 331 2 50 3 13 3 17 3 58 9 509 335 2 35 2 59 2 52 3 40 10A 1 20 1 35 1 10 1 45 1 39 10B 387 1 22 1 38 1 20 1 44 1 58

11 192 5 13 2 26 2 43

12 247 169 5 11 (5 56) (5 50) 2 10 2 12

13 250 176 4 9 (5 11) (4 49) 2 1 2 14 14 152 (7 48) 5 44 5 45 2 17 1 40

159 (7 29) 7 4 49 2 32 2 19

16 161 (7 25) 5 46 3 16 2 57 3 12

17 224 (6 25) 5 1 5 4

7 (6 5) 1 49 1 58

18 205 2 16 2 27

19 271 4 45 5 39 2 0 2 5 20 218 (7 20) 2 20 2 25

21 228 (6 34) 2 15 2 33

22 173 (7 1) 5 7 5 18 (7 30) 7 5 38 2 39 2 47

23 233 (6 20) 5 15 4 41 (7 2) 2 27 2 33

24 132 121 (5 16) nr

25 150 3 22 3 21

26 132 (7 18) 5 06 3 33 4 12 27 253 215 6 59 (7 55) (7 37) 2 41 2 49

28 253 197 6 14 (7 54) (7 21) 2 30

29 127 nr (7 5) 3 31 3 59

30 131 3 29 3 52

31 125 3 56 4 1

32 118 4 9 4 30

33 250 174 10 6 (11 14) 3 32 3 53

34 155 123 (9 53) 35 253 166 7 42 nr (8 59) 3 2 3 17

36 253 172 6 39 (7 56) 2 46 3 5 37 348 242 9 32 (11 22) 3 41 3 43

38 119 nr nr nr

39 159 119 (13 5) (14 17) 40 170 10 19 (12 5) nr 6 38 7 31

41 98 (8 17) (9 56) 42 292 220 15 5 (18 0) nr 9 14 10 10 43 107 nr nr

44 136 119 7 34 . 7 32

45 251 167 12 49 (14 24) 8 33 9 1

46 105 nr nr

47 247 178 (16 9) (19 25) (17 52) 11 30 12 7

48 130 110 (16 16) 49 255 177 13 47 (15 38) nr 10 18 11 22

50 253 181 13 57 (17 15) (15 2) nr 10 17 11 26

100 nr nr nr nr

52 87 75 nr nr

53 203 137 nr nr nr nr 10 43 12 39

4 Figures in italics indicate derived temperature limit for determination under asbestos pads (see section 6.1, a).

5 Figures in parentheses indicate temperature rise reached after the test fire was shut off.

6 “nr” indicates that a given temperature was not reached.

7 Cotton waste placed over thermocouple.

the joints between bricks and not necessarily

continuous through the wall. On the fire-exposed

side, the cracks were relatively smaller.

The t ine at which a temperature rise of 325 deg

F occurred over cracks is given in table 9. This

limit was reached before 5 hr only in the tests of walls 15 and 16. Wall 15 was laid up in portlandcement mortar and tested restrained. Due to mortar that did not adhere to the trowel and

spread readily, the wall had a number of small

holes, the high temperature rise occurring over one of them with a wad of cotton covering the

thermocouple.

For wall 16, laid up in lime mortar and tested

unrestrained, the temperature rise limit was

reached at 3 hr 16 min over a large diagonal

crack in the upper part of the wall. For wall 17. tested restrained, and wall IS under load, both

17
TEMPERATURE

IN

DEGREES

CENTIGRADE

TEMPERATURE

IN

DEGREES

CENTIGRADE

TIME IN HOURS

Figure 5. Temperatures in fire-endurance tests of 4-in. unplastered walls 3, 5, and 6.

TEMPERATURE

IN

DEGREES

FAHRENHEIT

TEMPERATURE

IN

DEGREES

FAHRENHEIT
TEMPERATURE

IN

DEGREES

CENTIGRADE

TIME IN HOURS

Figure 7. Temperatures in fire-endurance test of 4~in. pilastered walls 10A and, 10B.

TEMPERATURE

IN

DEGREES

FAHRENHEIT
DEFLECTIONS

IN

INCHES

AWAY

FROM

FIRE

TOWARD

FIRE,

AWAY

FROM

FIRE

TOWARD

FIRE

TOWARD

FIRE

I 2 3 4 5 G

TIME IN HOURS Figure 9. Deflections of solid walls of clay and shale bricks.

Figure 10. Unexposed side of f-in. wall 7 after fire-endurance and hose-stream tests.

20

COOLING

\

'

\\

-

COOLING
TEMPERATURE

IN

DEGREES

CENTIGRADE

TEMPERATURE

IN

DEGREES

CENTIGRADE

- 2100

2000

1900

LdI

1800 g

1700 ^

1600 2

1500 If) hi 1400 W

cc 1300 £3

Id 1200 Q

1100 i=

1000 Jji 900 ^

800 ^

111 700 Q. 600 §

500

TIME IN HOURS

Figure 12. Temperatures in fire-endurance test oj solid clay-brick wall I J.

21

TEMPERATURE

IN

DEGREES

FAHRENHEIT
TIME IN HOURS

Figure 13. Temperatures in fire-endurance test of plastered solid clay-brick wall 37.

Figure 14. JJnexposed side of 8-in. unrestrained wall If at end of 6-hr fire test.

22

TEMPERATURE

IN

DEGREES

FAHRENHEIT
laid up in lime mortar, no crack having an opening

over in. was observed. As the object of the

test in the unrestrained condition was mainly to determine stability, the low limit of temperature

rise for wall 16 may not be significant.

The cracks formed in walls tested unrestrained were wider and in greater number and extent than

for those tested restrained within the panel frame.

For the latter condition, they seldom had width

exceeding he in. with the present group of walls,

while for the unrestrained condition a number of cracks had openings of %6 to %6 in. on the unexposed side of the wall. As tested restrained,

there was little difference in the matter of cracks

observed as due to the three types of mortar used,

namely, cement, cement-lime, and lime. This

also applies for the effect of brick materials from

the three sources, CLM, CLI, and SHW. Tested

unrestrained, cracks of the greatest extent and

width were evidenced for wall 16 of clay bricks

laid up in lime mortar and for wall 23 of shale

bricks in cement -lime mortar.

In some tests, the central part of the wall slid inward from %6 to % in. at the second to sixth course from the base due to the force of the in- ward deflection. However, resulting openings were not over % in. wide.

Openings on the unexposed side were formed

between the wall under test and the frame,

occurring at the base of unrestrained walls, at the

base and top for the loaded walls, and also at the

sides for walls tested restrained. At the sides,

these openings did not exceed Ks in. and apparently

had no effect on the performance of the wall.

At the base of the wall, there were openings up

to / in. at the outer face. While the lower edge

of the large cotton pad and excelsior box were

resting in most tests on the restraining frame at the base of the wall, no ignition or scorching from

these cracks at the bottom margin was noted.

This was probably due to an inward draft of cold

air where the crack communicated with the

furnace chamber.

Between the panel frame and the top of re- strained walls, openings up to % in. in width were formed at the outer surface. These closed up or became smaller as the fire-exposed face was

approached. The limited number of determinations made indicated temperatures at these openings up to the ignition point of wood or other ordinary combustible materials in immediate contact , at 2 y2 to 3 hr after the start of the test. It is unlikely that room contents would be in contact at the top of the wall. Further, wood in cornice molds,

generally applied only on plastered construction

and with the inner corner cut back, would not be

within 1 y2 or 2 in. from such an opening.

(6) Fusion and spalling effects. With walls of clay bricks from source CLM, there was no fusion

or spalling of bricks during a 6-hr fire test. The

fire-exposed side of such a wall after test is shown

in figure 15. With walls of clay bricks from source CLI,

there was considerable fusion and fluxing of the

bricks on the lower part of the wall where the

furnace temperatures were highest (fig. 16).

This began after 4-hr fire exposure, most of it occurring during the last hour of the 6-hr fire

Figure 15. Fire-exposed side of wall 11 of clay bricks from source CLM after 6-hr fire test
test. The depth of fusion was from % to 1 in. The softening point of this brick is near 2,100° F. The fusion, apparently had little effect on the

fire resistance of the walls. With walls of shale bricks (source SHW) the

fusion was limited to near the exposed surface

with little running of fused material (fig. 17). With wall 22 tested restrained there was spalling

of bricks on the fire-exposed side to depths of }i to y2 in. For wall 23, tested unrestrained, there was no spalling but there were cracks in the bricks

parallel with the surface at a depth of to 1}{ in. In figure 18 is shown the fire-exposed side of wall 37 after the 11 -hr fire test. It was built of clay br.cks from source CLM and had gypsum

plaster on both sides. The furnace temperatures

during the last 2 hr of the test were in the range

2,400° to 2,500° F. The fusion apparently

affected the mortar joints more than the bricks,

and the plaster before it sloughed off probably

also had a fluxing effect.

c. Concrete and Sand-Lime Brick Walls of 8-in. Thickness

This group comprises walls 25 to 36, of which 6 were large walls tested to 6 hr and 6 were small

walls tested for longer periods.

( 1 ) Surface-temperature rise. In no test was a temperature-rise limit reached on the unexposed

surface within 6 hr in the regular thermocouple

locations. In the test of wall 26, a temperature

rise of 325 deg F occurred at 5 hr 6 min over a hole in a mortar joint (table 9). For wall 27, of concrete bricks normally sea- soned, the temperature rise of 250 deg F under

the standard asbestos pad occurred at 6 hr 59

min (fig. 19). With wall 28, dried to constant

weight at elevated temperatures, the same limit was reached at 6 hr 14 min.

In tests of walls of sand-lime bricks, the surfacetemperature rise was slower than with bricks of other types, although for the tests with bricks

from source SLD, this was due in part to bricks

wider than the standard 3%-in. width by Z2 to %

in. A temperature rise of 325 deg F occurred at

a crack 64 min after the fire was off in test of wall

29 of sand-lime bricks from source SLP (fig. 20).

In fire test of wall 33, of sand-lime bricks from

source SLD and seasoned under room conditions

for 77 days, the limit of 250-deg F temperature

rise on the surface was reached at 10 hr 6 min

(table 9). With similar wall 35, dried at higher

temperatures, the same limit obtained at 7 hr 42

min. With wall 36, buillt of sand-lime bricks

from source SLO, having width near the standard

3% in. and dried at the higher temperatures, the

250-deg F surface-temperature limit was reached

at 6 hr 39 min.

(3) Temperature limits within wall. For walls

of concrete bricks normally seasoned, the time

at which an average temperature rise of 325 deg was reached at the midplane of the wall ranged

from 2 hr 41 min to 3 hr 33 min (table 9). For

wall 28, which was dried to constant weight, the

limit was reached at 2 hr 30 min. In tests of five walls of sand-lime bricks nor- mally seasoned (walls 29 to 33), the rise of 325

deg F in the wall was reached at an average of 3 hr 43 min. As dried at elevated temperatures,

this was reduced to 3 hr 2 min for wall 35 of bricks

j from source SLD, and to 2 hr 46 min for wall 36, i built of the smaller bricks from source SLO.

(3) Load-carrying ability and lateral deflections. Wall 28, of concrete bricks from source COE, was

tested under load of 160 lb/in. 2

, which was sus- tained in a fire test of 6 hr 17 min (table 9). A

pier cut from the wall after test had a compressive

strength of 430 lb/in. 2 and that of the companion i pier not subjected to fire test, 940 lb/in. 2 (table 5). Wall 32, of sand-lime bricks from source SLD,

carried a load of 146 lb/in. 2 during a 6-hr fire test. The strength of the companion masonry pier was

710 lb/in. 2 and for a pier cut from the wall after the fire test, 450 lb/in. 2 The maximum lateral deflection during the fire test was 0.70 in. Wall

46 of sand-lime bricks from the same source supported a load of 160 lb/in. 2 during an 8-lir fire test. The lateral deflections of solid walls of concrete and sand-lime bricks are plotted in figure 21. , There was no collapse of either restrained or unrestrained walls from excessive deflections. As 11 indicated in par. b (4) above for clay and shale

brick walls, the average top deflection at the end

of 6-hr fire tests of unrestrained walls, was about

four times the center deflection of restrained walls.

(4) Cracks and other fire effects. The extent of cracking of the walls during test was about the same as for the 8-in. clay- and shale-brick walls. For those tested restrained, cracks in the body of i the wall were rarely more than Z6 in. in width.

However, as tested unrestrained, many diagonal

cracks were formed with openings in the range

Zi to % in. The openings that developed between wall and

frame were not of such extent as to affect the fire resistance. The same applies for horizontal dis- placements of brick courses with reference to each other. For concrete-brick walls tested for 6 to 8 hr,

there was fusion of the bricks to a depth of % in., but the fused material remained largely in place

(fig. 22). A few bricks spalled to a depth of % in. The bricks were, in general, dehydrated and weak

for a depth of 2*to 3 in. from the fire-exposed side,

j With walls of sand-lime bricks tested for 6 hr,

there was no fusion of brick or mortar (fig. 23).

For longer test durations up to 10 hr, the mortar

in the joints fused to depths of 1 in. The fire- exposed bricks were crazed and cracked to the extent of falling to pieces under light impacts

after removal from the wall.

d. Solid Walls of 12-in. Thickness

The pres®it group of 16 tests (walls 3S to 53,

table 9) was made with 12-in. walls, one or more

of which were built of bricks from the sources

24
Figure 16. Fire-exposed side of wall 21 of clay bricks from source CLI after 6-hr fire test.
TEMPERATURE

IN

DEGREES

CENTIGRADE

2100

2000

1900

1800

1700

1600

1500 1400

900

800

700 600

500

400 300

200

100 I

26

TEMPERATURE

IN

DEGREES

FAHRENHEIT
TEMPERATURE

IN

DEGREES

CENTIGRADE

TIME IN HOURS

Figure 20. Temperatures in fire-endurance test of 8-in. sand-lime brick wall 29.

TEMPERATURE

IN

DEGREES

FAHRENHEIT
Figure 23. Fire-exposed side of 8-in. sand-lime brick wall SO after 6-hr fire test. 28
represented in the present series of tests. Only

four of these walls were of the larger size. (1) Surface-temperature limits. With the four

large walls in the first group that were tested to

6 hr or less (walls 38, 43, 46, and 51), the average

temperature rise on the free surface did not exceed

119 deg F. This represents a rise far below the

permissible limit of 250 deg F, as determined under

the asbestos pads. Nor did temperatures go higher

than 220 deg F under the large cotton pad and excelsior box or over cracks. Typical time-temperature curves from these tests are given in figure 24. In tests of longer duration, made with walls of the smaller size, the information obtained on fire endurance based on temperature rise is limited by

failure of some of the walls under load or ending

of the test before the limiting temperature rise was reached. For clay-brick wall 40, that had

been dried to constant weight, the limit of 250 deg

F average rise was reached at 10 hr 19 min (fig. 25).

For shale-brick wall 45, seasoned under room conditions for 77 days, the limit was reached at 12

hi’ 49 min.

The fire-endurance limit based on average

surface-temperature rise was reached for 12-in. concrete-brick wall 47 at 16 hr 9 min. This wall was of the small size and seasoned under room

conditions for 82 days. With similar walls 49

and 50, that were dried to constant weight at higher temperatures, the limit was reached at 13 hr 47 min and 13 hr 57 min, respectively.

The surface-temperature limits were not determined with 12-in. walls of sand-lime bricks

because wall 51 was tested only to 6 hi-, and walls

52 and 53 failed under load before the limit was

reached.

The results of all fire tests of 12-in. walls in the

smaller size should be applied with due consideration for the more favorable conditions attributable

to size as compared with those of walls having

dimensions approximating constructions in buildings. This will be given consideration in evaluating the results of the tests.

(2) Temperature rise in wall. The average temperature rise of 325 deg F 4 in. from the unexposed

side was not reached in any of the tests of large

walls terminated at 6 hr. For wall 40, of clay

bricks from source CLM, which was dried to constant weight at temperatures in the range

160° to 180° F, the limit of average temperature

rise in the wall was reached at 6 In- 38 min. With

wall 44, of clay bricks from source CLI, and with

wall 45, of shale bricks, both seasoned under room

! conditions, the limits were reached at 7 hr 32 min

and 8 hr 33 min, respectively.

For wall 42, of clay bricks with lime plaster on

the fire-exposed side, the temperature-rise limit

in the wall was reached at 9 hr 14 min. Although

the plaster fell off during the first 12 min of the

test, it apparently had retarded drying of the

wall, which was tested at the age of 41 days.

In the tests with walls of concrete bricks, the

temperature-rise limit in the wall came at 11 hr

30 min for wall 47 seasoned under room conditions

and at 10 hr 18 min and 1 0 hr 17 min, respectively,

for walls 49 and 50 that were dried to constant

weight at higher temperatures. The limit of wall- temperature rise was reached at 10 hr 43 min

with wall 53 of sand-lime bricks, which was also

dried to constant weight at the higher

temperatures.

Because the limits of wall-temperature rise were obtained with walls of the smaller size, the

determinations are subject to the same limitations as indicated above for limits of temperature rise on the surface.

(5) Lateral deflection. The maximum deflection

of clay-brick wall 43, tested restrained, was near

2 in. and the outward deflection at the top of wall

38, tested unrestrained, was about 8 in. at the

end of the fire test (fig. 9). A view of the tested

wall is given in figure 26. With the concrete and

sand-lime brick walls tested restrained, the center

deflection did not exceed 1.3 in. (fig. 21).

The deflections of the 12-in. walls of 1 1 -ft height, as tested for 6 hr, were not such as to seriously endanger stability or decrease to significant extent the ability of the walls to support

the working load. Near the end of the test, the

deflections were constant or decreasing, hence a longer fire exposure may not be critical from this standpoint.

(4) Cracks and imperfect joints. There were

Only very fine cracks on the unexposed side of

12-in. walls, except that for the ones that failed

under load larger cracks began to show at 10 to

15 min before failure. Openings on the unexposed

side between frame and wall had a maximum of % in. width with wall 43, for which the maximum

center deflection was near 2 in. (fig. 9). With

walls 46 and 51 having lower deflections (fig. 21).

these openings were not noticeable.

Steam and hot gases issued from holes in mortar

joints, but no temperatures higher than 220 deg F

were indicated over them for the large walls tested

to 6 hr or less. (5) Fusion of brick and mortar. In the fire tests of large walls limited to 6 hr, there was no

appreciable fusion of wall material except for wall

43, of clay bricks from source CLI, where there was

fusion and fluxing of the bricks to about the same

extent as for the 8-in. walls of bricks from this source. In tests of longer duration, there was

more fusion, depending upon the brick material

and duration of the tests. Although clay brick from source CLM had a relatively high softening point, there was a limited

amount of fusion in tests of the longer durations

(fig. 27). For wall 44, of clay bricks from source CLI, most of the fire-exposed course was fluxed

away during the 10 hr 21 min test. With shale

bricks, the fusion effect was of intermediate degree

(fig. 28).

With concrete and sand-lime bricks, the fusion

effects were dependent upon the sand anil other

aggregates used. With walls 47 and 48, of eon29
TEMPERATURE

IN

DEGREES

CENTIGRADE

TEMPERA

I

URE

IN

DEGREES

CENTIGRADE

Figure 24. Temperatures in fire-endurance test of 12-in. concrete brick wall 46.

TIME IN HOURS

Figure 25. Temperatures in fire-endurance test of 12-in. clay brick wall 40.

30

TEMPERATURE

IN

DEGREES

FAHRENHEIT

TEMPERATURE

IN

DEGREES

FAHRENHEIT
31
Crete bricks from source COD, tested for 16 hr

4 min and 12 hr 30 min, respectively, there was

no general fluxing of the bricks. There was more

fusion of the concrete top member of the loading

frame (fig. 29). In the test of wall 49, most of the course on the fire-exposed side fused and flowed

into the furnace pit. The bricks for these walls

Avere from the same plant, but those for wall 49

Avere from a later delivery. There Avas also fusion

of the fire-exposed course in the test of Avail 50 of concrete bricks from source COE (fig. 30).

With walls of sand-lime bricks, the fusion effects Avere about the same as for concrete-brick Avails tested for comparable durations.

In the tests of the longer durations, the mortar

fused to depths up to 2 in. However, it remained

largely in place Avhere supported by bricks that

had not fused.

It is to be noted that in these tests the furnace

temperatures after 8 hr Avere raised to a ceiling of 2,500 deg F at 10 hr 40 min. The prescribed procedure [6] Avas later revised so that the 2,300 deg F

reached at 8 hr remained as the ceiling for tests of

longer durations. Hence, according to the later procedure, there Avill be comparatively less fusion

of Avail materials in fire tests extending beyond 8 i hr.

(6) Failure under load. The ability to carry

1 the applied working load in tests of long duration

Avas limited by fusion and decided loss in strength i of brick and mortar in the course on the firej exposed side. The unexposed side of Avail 44, of

clay brick from source CLI, is sliOAvn in figure 31

after failure under load, and the fire-exposed side

of sand-lime brick wall 52 is shoAvn in figure 32. For 12-in. Avails, the ability to carry load Avas determined with walls of the smaller size. It Avas deemed impractical to subject the large Avails to

fire tests of the required long durations, considering the damage and possible inoperative condition

that, would result for furnace and loading equipment. HoAvever, the size of Avail specimen tested

had a considei’able bearing on the results obtained,

due account of which Avill be taken in making the

e\T aluation.

Figure 28. Fire-exposed side of 12-in. shale-brick wall 1+5 after 12-hr 50-min

fire test.
Figure 29. Fire-exposed side of 12-in. concrete-brick wall f7 after 16-hr f-min fire test.
Figure 31. Unexposed side of 12-in. wall 44 of clay * bricks from source CLI after failure under load at | 10 hr 21 min in fire-endurance test.

Figure 32. Fire-exposed side of 12-in. sand-lime brick wall 52 after failure under

load at 9 hr 57 min in fire-endurance test.

34
6.3. Results With Walls of Hollow Designs

The schedule of tests with walls having one or more unfilled spaces in the wall thickness is given

in table 7, and the results of the tests in terms of

fire-endurance limits are given in table 10. The

walls were all built of clay or shale brick.

a. Hollow Walls of 8-in. Thickness

In this group are included 8 all-rolok walls

(walls 54 to 61) and 2 (walls 62 and 63) of the

rolok-bak pattern (fig. 1, designs D and E).

(i) Surface-temperature limits. The tests of all of the large walls (walls 54 to 59) were among the

first in the series before surface temperatures were

determined under the 0.40-in. -thick asbestos pads.

The time, however, at which an average 250-cleg

F rise was reached on the free surface was determined in all of these tests. From these the approximate times for the rise under the asbestos

pads, given in italics in table 10, were derived by

applying the 0.84 factor (section 4.1).

On this basis, the average time to reach the

250-deg F rise for the six unplastered walls, 54 to

59. was 2 hi’ 46 min. The minimum for any test was 2 In- 25 min. Typical time-temperature

curves are given in figure 33. These results might be considered qualified by

lower limits indicated over cracks for walls 57,

58, and 59. The hot spots were actually over

holes in the vertical mortar joints, which were

not as well filled for bricks set with the 4-in. di- mensions vertically as for the conventional method

with bricks laid flatwise. This was due in part

to less experience of the masons with this method

and also less care in pointing of joints than would

be required for unplastered walls in building

construction.

The occurrence for wall 58 of the limiting temperature rise at 2 hr 14 min under the 3- by 3-ft cotton pad of 3%-in. thickness can be taken as due

largely to the greater heat insulation over the area

adjacent to the thermocouple as compared with

that given by 6- by 6-in. asbestos pads of 0.40-in.

thickness.

With all-rolok walls 60 and 61 plastered on both

sides, the limit of average temperature rise on the

unexposed surface was reached soon after 5 hr. These tests were with walls of the smaller size,

and considering the air space, the results may

have been unduly affected by cooling from the

borders.

Walls 62 and 63 were of the rolok-bak design

with bricks laid flat for the face course and on

edge for the backing (fig. 1-E), the backing as plastered being exposed to the furnace fire. For

wall 62, the limit of surface-temperature rise came at 4 hr 58 min (fig. 34) and for wall 63 at 4

hr, all lime plaster on the latter falling off during

the first 15 min of the test. The gypsum plaster on wall 62 remained in place for 2 In-

, but at 4%

hr practically all had fallen off. For these walls

also the results may be subject to qualification due

to cooling from the borders, considering the con- tinuous air space between the facing and backing.

(2) Temperature limit's in wall. The limiting

temperature rise in the wall, as given in the last columns of table 10, is taken at 250 deg F for th> average and 325 deg F at any thermocouple location. This is lower than the comparable limits

for solid wall constructions (table 9) because parts

of combustible members projecting into the air space ignite and burn more readily than those

embedded in a solid wall. The average time for the present limit in tests of unplastered 8-in. rolok walls was 1 hr, with

minimum in any test of 54 min. For the two

plastered walls, 60 and 61, the average was 1 hr

42 min.

( 3) Restraint, loading, and lateral deflection*. Of the 6 large 8-in. all-rolok walls, 2 were tested

restrained within the panel frame and 3 unrestrained. One of shale bricks was tested under

load of 160 lb/in. 2 of gross area, which was sus- tained throughout a 6-hr fire test (fig. 35).

As for solid walls, the lateral deflection as tested

restrained was indicated as greater than with the

wall under load (fig. 36). The deflection at the

top of unrestrained walls was 2 to 4 times the

center deflection of restrained or loaded walls, the

relation being less consistent than in tests with

solid walls. There was no collapse due to deflection with walls of 11 -ft height and exposed to

fire for periods considerably beyond their fire- endurance limits as determined by the temperature rise on the unexposed side.

(4) Cracks and otherfire eflects. For walls tested

restrained, the cracks were hardly noticeable, and

between wall and frame there were openings on

the unexposed side up to % in. In the wall tested

under load, cracks opened up to Ys in., and in those tested unrestrained, up to /j 6 in. These

were generally inclined and through the mortar

joints.

The fusion effects with walls of clay bricks from

source CLI, tested for 6 hr, were about the same

as for solid walls of bricks from the same source

(fig. 16). However, there was no fusion of bricks

from this source in a wall exposed to fire for nearlv

4 hr (fig. 37).

b. Hollow Walls of 12-in. thickness

This group comprises six walls, 64 to 69. of

several rolok designs (fig. 1, F to lv). They were

all built of clay bricks from source CLM.

( 1 ) Surface-temperature limits. In the test of

all-rolok wall 64, the temperature-rise limit was

not reached, but with wall 65 of alternate rolok

design, the 250-deg F rise under the asbestos pad came at 5 hr 7 min (fig. 3S). For wall 67 of the

flat-bond rolok design and plastered on both sides,

the limit was reached at 10 hr 12 min. this result being apparently affected by cooling from the borders through the continuous air spaces. The same

applies, although possibly in less degree, to the
Table 10. Results of fire-endurance tests of hollow walls of clay or shale brick

Walls having minimum lateral dimension of 10 ft and area of 100 ft2 conform to present requirements of ASTM Standard E119

Wall Nominal

thick- ness

Wall Wall design Brick

Plaster Restraint or loading during test

Age at time

of test Why ended

Severity

or test area (fig. No.) symbol

Fire-ex- posed side Unexposed

side

jjuration of furnace exposure

54

in.8

ft2 171 All-rolok 1-D . CLM None None

Unrestrained Days

40 hr6 min

1 Set limit . Percent

101.2

55 8 171 do CLI -do -do do 34 3 58 High wall tern- 101.0

56 8 176 do CLI -..do. --do.- Restrained.. 38 6 1 perature.

98 0

57 8 176 do CLI --do -.do.- ___ do 40 6 1 do 99.2

58 8 171 do SHW .do ..do Unrestrained.. 53 6 1 do 99.9

59 8 163 do SHW - - do - -do 160 lb/in.L.. 32 6 0 do 100.2

60 8 17.4 ..do CLM Lime Lime Restrained... 42 8 0 High wall tern- 99.2

61 8 17.4 . do ... CLM Gypsum.

Gypsum.do 45 6 1 perature. do 98.7

62 8 16. 7 Rolok-bak 1-E__ CLM _ do None ... 160 lb/in. 2 43 6 20 do.. 99.4

63 8 16. 7 do CLM Lime--- - 46 5 30 98.4

64 12 171 All-rolok 1-F. CLM None - .do Unrestrained. 98.2

100 5 13 Equipment fail65 12 17.4 Rolok 1-0 _. CLM --do -do Restrained 47 8 0

ure. High wall tern- 98.3

66 12 17.4 -do CLM Gypsum.

-_do

Gypsum. _ do.. 46 8 0 perature.

100.

67 12 17.4 Rolok 1-H CLM --do do 46 10 50 High wall tem- 100. 1

68 12 16.7 Rolok-bak 1-.T CLM None None

Unrestrained.. 41 12 20 perature. do 102.

69 12 16.7 Rolok-taced 1-K CLM - - do -do 160 lb/in. 2 41 10 1 do... 100. 1 70 10 163 Cavity 1-1, CLN -do - . do 125 lb/in. 2 48 1 17 Wall collapsed.

101.5

71 10 164 do CLN -do._ _- 33 5 18 High wall temperature. do

100. 0

72 10 160 do CLN ...do -do Restrained 41 5 3 100.0

2400

2300

2200 2100

2000

1900

1800

1700

1600

1200

1100 1000 900

800

700

600

500 400

300

200

100

1500 (/) Li 1400 yo

TIME IN HOURS

Figure 33. Temperatures in fire-endurance test of 8-in. all-rolok wall 58.

36
Table 10. Results of fire-endurance tests of hollow walls of clay or shale brick.—Continued

Wall or

test

Temperature rise at unexposed surface Time of temperature

rise in wall 4 in. from

unexposed surface Average at end of test Time of average 250-deg F rise Time of 325-deg F rise at one location

Asbestos Free Asbestos Free Cotton Excelsior Asbestos Free Over 250-deg F 325-deg F pad surface pad surface pad box pad surface crack average maximum

° F ° F hr min hr min hr min hr min hr min hr min hr min hr min hr min

i 2 25 2 52 3 24 0 .54

• 2 45 3 16 3 42 1 0 1 10

379 2 55 3 29 4 25 1 4 1 10

57 410 2 37 3 7 3 49 2 1 47 0 56 1 2

58 420 2 i? 3 13 2 14 2 42 3 33 2 21 1 5 1 5

59 390 3 13 3 50 2 57 4 2 4 15 <N G 0 59 1 05 60 500 318 5 2 7 26 1 45 1 51

61 343 253 5 13 5 57 1 39

62 414 234 4 58 nr nr 1 52 1 37 63 447 277 4 0 5 08 * (6 13) 0 57 1 0

04 114 nr (5 32) 3 41 2 48

462 281 5 7 7 5 7 47 2 45 2 41

66 166 130 (9 7) 4 7 3 47

67 320 219 10 12 (11 32) nr 5 20 5 31

68 359 260 10 42 12 2 nr 4 56

69 359 218 8 52 nr 4 58 5 28

70 17 nr nr

71 252 5 17 nr 1 48 2 6

72 264 4 56 nr 1 25 1 28

1 Figures in italics indicate derived temperature limit for determination under asbestos pads (see section 6.1, a).

2 Cotton waste placed over thermocouple.

s “nr” indicates that a given temperature was not reached.

i Figures in parentheses indicate temperature rise reached after the test fire was shut off.

IdO

<

o:a

I-z

Ido

(/) Id

IdXo

IdQ

Id

a:D

I-<

IXhi

Q.£

Idh

2400

2300

2200

-2100

2000

1900

1800

1700

1600

1500

1400 1300

1200

IIOO lOOO 900

800

700 600

500

400 300

200

100

TIME IN HOURS

Figure 34. Temperatures in fire-endurance test of 8-in. rolok-bak wall plash red on tin firr-c.r

> >
Figure 36. Deflections of hollow walls of clay and shale bricks.

38
TEMPERATURE

IN

DEGREES

CENTIGRADE

Figure 37. Fire-exposed side of 8-in. all-rolok wall 55, of clay bricks from source CLI,

after 3-hr 58-min fire exposure.

TIME IN HOURS

Figure 38. Temperatures in fire-endurance test of 12-in. U'all 65 of alternate rolok design.

TEMPERATURE

IN

DEGREES

FAHRENHEIT
10-hr 42-min limit for rolok-bak wall 68 and the

8-hr 52-min limit for rolok-faced wall 69.

(2) Temperature limits in wall. The times when

an average temperature rise of 250-deg F occurred

in the air space next to the unexposed side or a

rise of 325 deg F at any thermocouple location, are given in the last two columns of table 10. As

for surface-temperature limits, the results with

the small walls, and particularly with those of the

flat-bond rolok and rolok-faced designs, are subject to qualification because of cooling from the

borders through continuous unobstructed air spaces.

(3) Cracks and other fire effects. In none of the

tests was cracks noted that would affect the fire resistance of these 12-in. walls. The top of wall

64, tested unrestrained, deflected outward about

6 in. (fig. 36).

The walls were built of brick from source CLM,

showing a relatively high softening point, and

there was no fusion causing flow of brick material.

Figure 39 shows the fire-exposed face of wall 67

of the flat-bond rolok design after 10-hr 50-min

fire exposure. The plaster had fallen from the

fire-exposed side during the first 2 hr of the test. In figure 40, showing the backing side of rolokbak wall 68 fire-exposed for 12 hr 20 min, fusion

and flow of mortar is seen in joints between bricks

set on edge, but none in the brick material.

c. Cavity Walls

Three fire tests were conducted with cavity-type

walls (fig. 1-L), consisting of two brick wythes I with a 2-in. air space between them, spanned by i Z-shaped wire ties. They were built of clay brick

from source CLN laid up in 1 :1 :6 cement-limesaml mortar. As the width of the bricks was 1

little more than 3% in., the actual thickness of the I walls was in the range 9% to 9/ in.

(.1 ) Temperature-rise limits. The time at which

an average rise of 250-deg F was reached under

the asbestos pads was 5 hr 6 min, taken as an

average for walls 71 and 72. The time-temperature curves for the former are given in figure 41. For the same walls, the 250-deg F rise in the air space was reached in an average time of 1 hr 36

min. However, wood joists usually project into

walls no more than 3% in. for bearing purposes

and would be almost embedded. Accordingly, the

permissible average rise of 325-deg F, same as for

solid walls, might apply, which rise was reached

in 2 hr 10 min and 1 hr 43 min, respectively, for the two walls, or an average time of 1 hr 56 min.

(2) Loading and deflection. Wall 70, subjected

to fire test under load of 125 lb/in.2 of gross area,

failed because of load and deflection at 1 hr 17 j min, the center lateral deflection before failure

| being over 3 in. The brick material had a coefficient of expansion within the lower range for

40

Figure 39. Fire-exposed side of 12-in. flat-bond rolok wall 67 after 10-hr 50-min

fire exposure.
Figure 40. Backing side of 12-in. rolok-bak wall 68 after 12-hr 20-min

fire test.

UJQ

a.O

H

Z

u

LJD

Z

UJ

ITIME IN HOURS

Figure 41. Temperatures in fire-endurance test of cavity walls 70 and 71 of clay bricks from sou-cc Cl X

41

TEMPERATURE

IN

DEGREES

CENTIGRADE
I burned clay, and the early failure was apparantly

attributable to the cavity design.

Wall 71 was loaded to an average of 80 lb/in. 2 on

the wythe exposed to fire and 28 lb/in. 2 on the

unexposed wythe, the average load of 54 lb/in. 2 being applied 1% in. off-center toward the fire- exposed side. This is representative of the load on an exterior 10-in. cavity wall from the live and

dead load of floor, roof, and wall constructions.

The wall carried the load thus applied during a

fire test of 5 hr 18 min, although it deflected to- ward the fire a maximum of 3.3 in. (fig. 26).

(3) Cracks and, often joints. One horizontal

crack on the unexposed side of wall 72 opened to / in., otherwise none with an opening over in. was noted. The workmanship in building the

walls was good, with joints well filled and pointed.

6.4. Temperature Rise After Test

For the tests in which the data were obtained,

table 11 gives the average surface-temperature

rise at the end of the test when the fire was shut

off and the subsequent highest rise of average

surface temperature.

It is seen that with the test continued to the

fire-endurance limit of the wall, as indicated by an

average temperature rise under the asbestos pads

near 250 deg F, the subsequent rise for 4-in. wall

3 increased it to 498 deg F and for the 8-in. walls

it was increased to the range 374 to 414 deg F. For 4-in. wall 4, the fire exposure ended at 45

min, and the subsequent rise was to 334 deg F. For 8-in. walls 24 and 34, the test was stopped

about 1 hr short of their fire-endurance limits,

and the subsequent rise under the asbestos pads was to 348 and 304 deg F, respectively.

For 12-in. walls 40, 45, 49, and 50, the tests were

continued to then- fire-endurance limits as indicated by an average temperature rise under the

asbestos pads near 250 deg F, and the subsequent

rise increased it to the range 365 to 399 deg F. In the test of 12-in. clay-brick wall 41, stopped at

8 lrn, the temperature rise to the end of the fire exposure and subsequently was minor. Continued

closer to the fire-endurance limit (tests 39, 48,

1 and 66), the maximum rise ranged from 282 to Uj 373 deg F. In all of these tests, the walls remained in front

of the furnace with the fuel supply shut off but

with the fan supplying air for combustion kept on. Although the furnace temperature fell rapidly, for II considerable periods it was at levels substantially

above the temperature on the unexposed surface,

j The temperature rise on the latter was also due to higher temperatures on planes within the wall,

which, as the cooling progressed, might also be | higher than those on the side that had been exposed

to fire.

6.5. Ignition of Cotton and Excelsior Pads

In most of the fire tests of large walls, boxes

3 by 3 ft by 3% in. deep, filled either with cotton or wood excelsior, were placed against the lower por- jl tion of the unexposed surface. The box containing cotton was open on one side, with the cotton

in direct contact with the wall. The excelsior

box was closed with its side of /4 -in. pine or %-in. cypress boards in contact with the wall. A

thermocouple was placed between the wall and

the center of the pad.

Table 12 gives the record of evidence of ignition or nonignition and the corresponding temperatures

under the pads. In tests for self-ignition of cotton j| and wood, some smoke is given off before there is 1 ignition as evidenced by flame or glow. In some

of these tests, however, the observation indicating

Table 11. Surface-temperature rise after fire test

Wall or

test Wall design Brick material Nominal

thickness

Duration

of fire exposure

Temperature rise at end of test Final average temperature, rise

Under as- bestos pad On free surface

Under asbestos pad On free surface

Time Rise Time Rise

in. hr min 0 F 0 F hr min 0 F. hr min 0 F

3 Solids Clay 4 1 10 260 212 2 5 498 2 2 336

4 __ _do do_. 4 0 45 113 1 1 7 2 0 334 1 50 295

12 do do - 8 5 10 247 1 09 7 43 41 4 7 10 270

1 13 do-- do.-- 8 4 9 250 176 6 35 411 6 10 978

24 do Shale 8 4 0 132 121 7 20 348 6 47 240

27 do Concrete 8 7 0 253 215 10 12 410 9 30 290

1 28 do do . . 8 6 17 253 197 10 5 377 8 45 284

34 do Sand-lime _ ... 8 8 0 155 123 12 13 304 11 50 202

35 do 8 45 253 166 11 27 377

374

10 55 954

1 36 do -- do 8 6 41 253 172 10 20 9 45 240

39 do Clay 12 a 36 159 119 16 25 373 15 42 227

1 40 do-_ 12 10 22 255 170 14 55 365 14 12 232

41 do do 12 8 0 98 11 30 108

45 do Shale 12 12 50 251 167 17 29 399 16 55 245

48 do Concrete. 12 12 30 130 110 17 53 282 17 37 192

1 49 do 12 13 55 255 177 18 20 367 17 26 240

1 50 do - 12 14 0 953 181 52 374 17 15 950

2 66 Rolok __ Clay 12 8 0 166 130 11 48 341 11 55 204

1 Dried to constant weight at temperatures of 160° to 180° F. 2 Plastered on both sides.

42
Table 12. Temperatures and notes on ignition of large 'pads

Wall

or

test WaU

design Brick

material Nominalthickness

Cotton pad Excelsior box

Time Temperature Note Time Temperature

— —1 Note

in. hr min ° p hr min o f

1 Solid,. Clay. 4 2 15 471 Slight, smoke... 2 15

1 do ...do 4 2 25 576 Glow.. 3 18

1 do --.do 4 6 01 End of test ... G 01

5 do Shale . 4 1 35 448 2 15 525

5 do -..do.- 4 1 54 1069 Glow 2 41 595 End of test. 5 do _-.do 4 2 41 2 45 507

6 do . do 4 1 40 356 1 40 394

6 ___ _do ..do 4 1 44 i 44 Load failure. 10A do ...do 4+pilasters 1 40 567 Smoking

10A do . .do ...do 2 07 One-third consumed . 10A do ...do -..do 2 30 End of test. . ...

10B . . .do Clay ...do 1 42 468 Smoking. ... _ .. . 10B do ...do ...do 2 03 Blazing _ 10B do -. do . .do 2 30 End of test..

14 do _--do__ 8 6 01 338 do

14 do___ .. ...do 8 6 48 452

14 do ...do 8 8 30 556 Burning.. __

16 do ...do ----- 8 6 01 313 6 01 16 _ ...do ...do 8 6 15 333 Slight smoke . 6 15 Slight smoke.

16 do ...do 8 6 40 7 55

16 do . .do 8 7 55 ently ignited at crack. crack.

17 do ...do 8 6 00 482 End of test. Burnt odor. 6 00 403 End of test. Slight smoke.

17 do .do.. 8 6 20 520 6 20 429

17 do .. do 8 6 25 Glowing 6 30 scorched.

22 do Shale 8 5 49 434 Decided burnt odor, no 5 49 394 Slight burnt odor, no

smoke. smoke.

22 do ...do 8 6 01 460 End of test .. 6 01 417 End of test. 22 do __do. -. .. 8 6 05 6 05

23 ..do 8 5 52 417 5 52 438

23 . do. __ -. 8 6 01 441 6 01 453

23 8 6 03 6 03

26 do Concrete . 8 6 02 205 End of test 6 02 210

26 do .. do.. 8 During nieht Burned up _ _

32 do Sand-lime. 8 6 00 212 End of test.. 6 00 201 End of test. 32 do ...do 8 10 35 356 No ignition . ... 10 35 258 No ignition. 32 do . .do.. . -. 8 Next, dav ___ .do -. Next dav Do.

38 do Clay. 12 5 200 End of test .. 5 51

1 38 ...do 12

! 46 ... do 12 6 01 207 6 01 190 46 do ...do— 12 10 34 201 No ignition 10 34 193 No ignition.

1 46 ...do. 12 Next dav -_- _do._ Next dav Do.

Sand-lime. 12 6 01 205 End of test 6 01 190 ol do ..do 12 12 00 194 No ignition. 12 00 191 No ignition. 12 Do.

58 Shale 8 3 00 482 Smoking. 3 55 462

58 8 3 10 526 Scorched at top .

58 do ...do 8 4 00 697 Glowing throughout 4 20 495 Blazed up.

58 8 6 01 6 01

59 8 3 50 502 Had ignited .. 3 40 Smoking.

59 8 4 24 Burning 4 18 Burning.

59 8 6 00 6 00

64 do Clay 12 5 13 185 _do 5 13 163 Do.

64 do ...do 12 8 25 214 No ignition 8 25 178 No ignition. 64 do ...do 12 Next day Slight discolor, no ignition. Next day Rosin rim, no ignition.

I

43
smoke was apparently made at or beyond the time

ignition took place. In other cases ignition took

place at cracks or open joints and with the thermocouple not in the immediate location it indicated

relatively low temperature.

With the time of heating here concerned, which

was in the range 1 K to 12 hr, there was no evidence

of ignition of the wood or cotton at temperatures

below 400° F. At temperatures in the range

400° to 450°, smoking sufficient to indicate

ignition or approach to ignition was recorded. In

the range 450° to 500° F, more conclusive evidence

of ignition was apparent. The above should be

taken as limited to the conditions that prevailed

in these tests.

7. Results of Fire and

Hose- Stream Tests

The results of the fire and hose-stream tests are given in table 13, with a fuller description of the walls tested in table 7. All of them, except

4-in. wall 7 and cavity walls 71 and 72, were built

in three or more sections bonded together and of

bricks representative of those in the walls subjected to the fire-endurance tests. The points of interest in these results pertain

to the performance of the wall in the fire test pre- ceding the hose-stream application and the

stability and structural integrity maintained

during the hose-stream application.

At the time most of the fire and hose-stream

tests were conducted, the specifications for fire

test of load-bearing walls had not been developed

and the procedure used in the hose-stream tests followed that for nonbearing walls and partitions.

As this did not require the walls to carry load

during the hose-stream application, an evaluation

is here made from this standpoint for the constructions that were tested.

j 7.1. Performance Under Fire Exposure

The fire exposure of 1 1m or less duration pre- ceding the hose-stream application did not approach

the fire-resistance of any of the walls thus tested. Wall 7 of 4-in. thickness (fig. 10) and cavity walls

71 and 72 were subjected to the hose stream after the full fire-endurance test, in accordance with

the optional procedure.

7.2. Stability and Integrity

None of the walls collapsed in the fire and hosestream tests. For those tested unrestrained, there was dislodgment of some bricks near the borders

in the wythe on which the stream was applied,

but no holes through the wall were formed (figs. 42 and 43). For tests in the restrained condition, ( all bricks remained in place (figs. 44 and 45).

The same applies for 10-in. cavity walls 71 and 72,

the one being tested under load and the other

restrained.

All walls were laid up in 1 : / : 6 or 1 : 1 : 6 cementlime mortar except one-half of wall 77, which was

laid up in \:%:Q cement mortar.

Table 13 . Results of fire and hose-stream tests of brick walls

Wall or

test Nominalthickness Wall

area

Wall design Brick symbol for respective sections

Restraint or Duration

Hose-stream application

Type Figure No.

loading during

test of fire exposure Duration Pressure

at nozzle

Results

1 7

in.4

ft 2 160 Solid 1-A_. CLN

hr

1 min25 min

2

sec 24

Ibfin. 2 30 ... No wall temp, above permissible limits or passage of hose

stream.

73 4 176 1-A CLM, CLI, SHW, Do. CON. SLP.

... do.. _ __

1 0 5 0 50

74 8 171 ._ .do l-B Unrestrained.. 0 59 5 0 50 Do.

75 8 176 do 1 -B CLM. CLI, SHW, Restrained 1 0 5 0 49 Do.

76 8 176 1-0 CON.SLP.SLD. CLM, CLI, SHW,

CON, SLP.

... .do _ ._

1 0 5 0 50 .. Do.

8 171 ...do .. 1 -D Unrestrained.. 1 0 5 0 41 to 46..._ Do.

78A 12 173 Solid 1 -C CON, SLP, SLD... Restrained.. 1 0 5 0 38 to 45.... Do.

2 78 B 12 173 . do 1 -C do.. 1 0 5 0 50 to 52 Do.

1 71 10 163 Cavity..

1 -L CLN 54 lb/in . 2 5 18 8 0 45 Do.

l 72 10 160 __.do 1 -L do .. Restrained 5 3 7 57 45 Do.

1 Hose stream applied at the end of the fire-endurance test.

2 Test 78B was made with the same wall as test 78A with top brick course removed so wall could be tested in unrestrained condition.

44
Figure 42. Exposed side of 8-in. solid unrestrained wall 74 after fire and hose-stream test.

MiiMlMliHiIMUF«

MliwtfttlMlMiiMlM»* *

sBitMiaitgiiaiiifti 9

Figure 43 . Exposed side of 8-in. all-rolok unrestrained wall 77 after fire and hosc-stnar test

45
Figure 45. Exposed, side of 8-in. all-rolok restrained wall 76 after fire and hose-stream test.

I

I

l

46
7.3. Load-Carrying Ability

a. Walls of 4-in. Thickness

Brick walls of 4-in. thickness are not generally

used for bearing purposes, and in the present tests

4-in. walls 7 and 73 were not loaded in the fire and

hose-stream test. Clay-brick wall 2 and shale-brick wall 6 of this thickness were each subjected to a load of 80

lb in. 2 in fire-endurance tests that were sustained

up to or beyond their fire-endurance limits as determined by temperature rise on the unexposed

side. At the end of the fire-endurance test, the

load on wall 2 was increased to 160 lb/in. 2

, which was sustained, the center lateral deflection being

2 in. According to the specifications for conduct of

fire tests [6], the fire exposure preceding the hosestream application need not exceed more than

one-half the fire-endurance limit, or for 4-in. walls,

30 to 45 min. At this time, the deflection of 4-in. loaded walls was indicated at 2 in. or less (fig. 9),

which would be considerably reduced by the hosestream application. Hence, it appears fairly

assured that the 4-in. brick walls in this series would have sustained a load of 80 lb/in. 2 during

the hose-stream test and subsequent load of 160

lb in. 2. The original strength of the masonry as tested in piers ranged from 1,170 to 1,876 lb/in. 2 (table 5).

b. Solid and All-Rolok Walls of 8-in. Thickness

Walls 74 to 77 were subjected to the hose-stream

test in the restrained or unrestrained condition

with maximum lateral center deflection for the

restrained walls of 1 to 1% in. at the end of the

1-lir fire test, and 0 to 0.40 in. on cooling after the

hose-stream application.

The original strength of the masonry for the

solid walls as tested in piers ranged from 510 to 1,530 lb /in. 2 of gross area, and of piers taken from

the walls after fire and hose-stream tests, from

390 to 540 lb/in. 2 For the all-rolok walls, the

original strength of the masonry in piers had a range from 440 to 1,470 lb/in. 2 (table 5). Considering the above and the low deflections

at the end of the 1-hr fire exposure and on cooling

after the hose-stream application, it appears that

the walls would have carried the 160-lb/in. 2 load

during the fire and hose-stream test and twice the

load, or 320 lb/in. 2

, on cooling after the test. It might be noted that 8-in. walls carried working

loads in fire-endurance tests for 6 to 8 hr (tables

9 and 10).

c. Solid and All-Rolok Walls of 12-in. Thickness

Two fire and hose-stream tests were made with

12-in. solid wall 78, one with the wall restrained,

the other unrestrained. The maximum deflection at the end of the 1-hr fire exposure was 0.80 in. and after the water application, 0.35 in. The

original strength of the masonry in piers ranged

from 480 to 1,040 lb/in. 2 In one comparison with

piers of concrete bricks, the original strength was

850 lb/in.2 and for the pier taken from the wall

after hose-stream tests 78A and 78B, 580 lb/in.2 (table 5). As for the 8-in. walls, the low lateral deflections

during test and the strength of the masonry

indicate adequate ability to carry the loads re- quired by the present testing procedure.

No fire and hose-stream tests were made with

12-in. all-rolok hollow walls because the required

resistance for the purpose was considered as shown by the tests of 8-in. walls of the same design

d. Cavity Walls

Cavity wall 71 was subjected to the fire and

hose-stream test under the load carried in the

preceding fire-endurance test and wall 72 in the

restrained condition following the 5 hr 3 min

fire-endurance test. The load carried during test was reapplied on

wall 71 after cooling following the hose-stream

application, but on further increase, it failed at a load 50 percent in excess of the load carried during

the fire test. Although this is short of the 100-

percent excess load to be carried, it is noted that

the wall had been exposed to fire for 5 hr 18 min

in the preceding fire-enclurance test as compared

with the 1-hr fire exposure required by the regular

fire and hose-stream test procedure.

7.4. Other Wall Designs

N'o fire and hose-stream tests were conducted

with various rolok and rolok-bak designs, the

fire-endurance tests of which were only with walls

of the smaller size (walls 62, 63, and 65 to 69,

tables 7 and 10).

8. Effect of Fire Tests on Strength of

Brick and Masonry

Although the condition of the construction

after the fire test has no bearing on the rating

based on performance in the test, it is informative

as to the possibility of reuse after fire. Representative samples of bricks were taken from the

walls after the fire tests, with which over 2,000

strength and absorption tests were made. Speci- mens of masonry were also cut from the walls of approximately the same size as the auxiliary

specimens laid up when the walls were built. Cracking of masonry and bricks from differential expansion and the stresses induced by the

fire exposure was an apparent cause of loss of strength. The effect on the brick materials as such varied with type of material and temperature.

For clay and shale bricks subjected to temperatures in a limited range above those at which they were fired in the kiln, there were indications of

gain in strength where not offset by other effects of the fire exposure.

The concrete and sand-lime bricks lost strength

due to dehydration of the bonding constituents

When subjected in the fire tests to temperatures

not greatly exceeding 212° F, there was an increase

in strength in some cases. This may have been

due to the resulting temperature and moisture

conditions.

47
8.1. Compressive Strength of Bricks

Table 14 gives the results for half-bricks tested

in compression on edge and table 15 the results

with tests on side or flatwise. Fairly representative samples were obtained except where the

bricks were fused and fluxed.

Table 14. Effect of fire tests on compressive strength of bricks tested on edge

Brick

Type of test Location of bricks Average

original strength

Effect of fire test

Symbol Material Number

of tests

Average

loss (— ), gain (+)

lb/in, 2 Percent CLM Clay . Fire endurance.. _ .. . . Fire exposed in 4-, 8-, or 12-in. solid walls 2 530 76 —14 8 CLM do Fire and water. ... ... Fire exposed in 4- or 8-in. solid walls. 1, 960 9 —13 9 CLM do Fire endurance.. ... ... .. Middle course in 12-in. solid wall 2, 560 7 —6 2 CLM -- __do do Unexposed in 8- or 12-in. solid walls.

2, 400 71 —2 9 CLM ___ _do Fire and water . ... Unexposed in 8-in. solid walls.

1 960 10 -f-11 5 CLI do Fire endurance . Fire exposed in 8- or 12-in. solid walls 2. 330 17 -18 5 CLI _ _do ... ... .do.. 2 330 13 —0 6 CLI do __ ___ _do 2 330 35 —4 2 SHW Shale do ... __ ___ Fire exposed in 1- or 8-in. solid walls o’ 400 25 —15 0 SHW .. _ do_ do Unexposed in 8-in. solid walls. _ 6 400 24 -17 0 SHW do Fire and water. ........ . do __. 6, 400 9 —11 2 CON Concrete-- .. Fire endurance Fire exposed in 8- or 12-in. solid walls 1, 530 33 —21 8 CON do. _ ___do _ _____ . 1 530 23 +7 0 COD do Fire endurance to 13 hr 55 min. . .

Fire exposed in 12-in. solid wall 2, 290 0) (2) COD do _do __ _ _ 2 290 14 —46 3 COD do. .. _ _._do __ Unexposed in l?-in. solid wall. 2,- 290 20 +16. 4 SLP Sand-lime Fire endurance. . Fire exposed in 8- or 12-in. solid walls 4. 720 31 -50.9 SLP do Fire and water.. Fire exposed in 4-, 8-, or 12-in. solid walls. _. ... 4, 720 10 -43. 0 SLP . ...do. Fire endurance.. __ 4, 720 22 —13. 9 SLP _ ...do Fire and water do . 4, 720 16 —21 8 SLP ..do.. Fire endurance __ __ _ 4, 720 50 —23 9 SLP do Fire and water do . 4, 720 21 -17. 1 SLD do Fire endurance. .. .. • Fire exposed in 8-in. solid walls . 2. 270 40 -45. 0 SLD do... do __ ___ Unexposed in 8- or 12-in. solid walls.

2, 260 48 +0.

SLD do Fire and water . do 1,690 15 +6. 3 CLM Clay Fire endurance. . . .. Fire exposed in 8- or 12-in rolok walls ...... 2, 560 24 +6.2 CLM do.. do _ __ 2. 560 17 +18. 8 CLM do ___do Unexposed in 8- or 12-in. rolok walls. . . 2, 560 19 +1.3 CLI do _ .do 2,330 27 +8. 5 CLI _do . do__ __ 2, 330 25 —0. 9 SHW Shale do _ __ __ Fire exposed in 8-in. rolok walls 5, 840 23 -12.6 SHW do ___ do _ ___ Unexposed in 8-in. rolok walls 5, 910 31 -13.0

1 No tests. 2 Fluxed. Table 15. Effect of fire tests on compressive strength of bricks tested on side

Brick Average

original strength

Effect of Are test

Symbol Material Type of test Location of bricks Number

of tests

Average

loss (— ), gain (+)

CLM Clay Fire endurance—. _ Fire exposed in 4-, 8-, or 12-in. solid walls. ... _. lb/in. 2

3, 140 29 Percent —11; 7 CLM . do .. .do . . .. . Unexposed in 8- or 12-in. solid walls ... _ _ 3, 170 32 -10.2 CLI . do .

.do. . . . . Fire exposed in 8- or 12-in. solid walls _ 2, 920 2,920

8, 610

8, 110

2, 780 2,780

2, 920

2, 920

2, 920

4, 630

4, 630

4, 630

4,630

4,630

2, 530

2, 580 3,280

12 -8. 8 CLI _ do ._ .do . Unexposed hi 8- or 12-in. solid walls 4 -4. 3 SHW Shale . _ .do . Fire-exposed in 4- or 8-in. solid walls 23 -14.9 SHW _ _ do Unexposed in 8-in. solid walls . 11 —22. 5 CON do ... Fire exposed in 8- or 12-in. solid walls _. 9 -47. 5 CON Unexposed in 8- or 12-in. solid walls. . _ 18 -19. 7 COD Fire exposed in 12-in. solid wall _ _ 0)

10

(

2

) COD Middle course in 12-in. solid wall ... -0. 8 COD Unexposed in 12-in. solid wall .... _ _ _ 10 -19.3 SLP Fire exposed in 8- or 12-in. solid walls .. 13 -33. 6 SLP Fire exposed in 4-, 8-, or 12-in. solid walls. _ 8 -14.

SLP Middle course in i2-in. solid wall .. ._ _ 9 -11. 7 SLP 25 +12.9 SLP ...do . .. .. .. ... . . * 8 -2.4 SLD 22 —27. 8 SLD do . _do Unexposed in 8-in. solid walls . 22 -9.4 CLM 6 +17.7 +2.2

-13.

CLM 3, 280

2, 920

6, 750

6, 920

5 CLI 11 SHW 11 +3.4 SHW 14 -7.4

i No tests. 2 Fluxed. 48
Although the results indicate a considerable

range in loss of strength as between bricks from

the different sources, in most cases the effect is not of a degree that would preclude reuse of the

bricks or masonry. However, other conditions,

such as the effect on the mortar and deflection

and cracking of the wall residting from the fire test, would also have a bearing thereon. 8.2.

Transverse Strength of Bricks

Table 16 gives the flexure strength of bricks as determined with whole bricks on 7-in. span.

The loss is seen to be much greater than for the

compressive strength. As many of the bricks were broken in the wall from the fire tests and

were not included in the samples taken, the actual

loss was greater than indicated in the table. Dismantling of the walls also indicated that

transverse rupture of the bricks, particularly

in header courses, was the most serious effect having a bearing on possible reuse of the construction after test. 8.3. Absorption

No detailed results of the absorption tests at ' given here, but in general the fire test reduced the

absorption. It did not appear that the change in absorption had a significant bearing on the possibility of reusing the bricks or masonry.

8.4.

Masonry Strength

In seven comparisons obtained from table 5 on

loss of strength of 8- and 12-in. solid masonry in the fire-endurance test, the average is 40 percent

For six similar comparisons obtained with walls

in the fire and hose-stream tests, the average loss was 40.5 percent.

Table 16. Effect of fire tests on the flexure strength of bricks

Brick Average

original strength

Effect of fire test

Symbol Material Type of test Location of bricks Number

of tests

Average

loss (—), gain (+)

CLM Clay Fire endurance. . __ Fire-exposed stretchers in 4-, 8-. 12-in. solid walls

Ib/in. 2 890 56 Percent -73.

CLM

CLM

___ _do_ .

- __do doFire and water . . Fire-exposed headers in 8- or 12-in. solid walls __ Fire-exposed stretchers in 4- or 8-in. solid walls 900

1,210

760

45

10

6

-12.fi -72.9 CLM do Fire endurance Middle’ course stretchers in 12-in. solid wall . . ... +4.7 CLM __do . - do_. _ _ 950

1, 180

1, 180

1, 180

1, 180 2,040

2, 020

2, 020

650 650

650

650

34

24

30

5

-2.0

—58. 4 -56.9 —99 2

CLI _do do CLI . . _do _do ___ _ _ CLI _do _ __ _do__ CLI __ _do - _do. . 1150

10

12

-25.2

-84.3 -49.8 +27.2 _S° 9

SHW Shale . .do _ SHW . _-_do. . _do . _ . _ _ SHW __do _do .... _ ___ . CON Concrete . __do _ 1822

*9 CON _ __do do —74 0 CON do Fire and water. CON _do -_do -_ __ _ _ —44 1 CON __.do Fire endurance. . Unexposed stretchers in 8- or 12-in. solid walls ... 650 23 -30. 1 CON __ _.do_ _ - _ _do 650 6 -35.2 CON _do Fire and water . . Unexposed stretchers in 8- or 12-in. solid walls 650 5 -19.3 COD _do__ _ Fire endurance to 13 hr 55 min _ _

Fire-exposed headers or stretchers in 12-in. solid wall 780 0)

10

(2) COD _do. _do - -. . _ 780 —S5. 2 COD . . _do. -- do_ __ _ 780 10 —66.

COD _do . do _ _ 780 10 —43. 1 SLP Sand-lime Fire endurance . _ _ . _ . Fire-exposed stretchers in 8- or 12-in. solid walls 930 17 -94.8 SLP do - ___do _ . _ _ _ _ __ Fire-exposed headers in 8- or 12-in. solid walls 930 23

8

-81. 4 SLP _do Fire and water. . _ Fire-exposed stretchers in 4-. 8-, or 12-in. solid walls 930 —89. 7 SLP - -__do.- . -- - --_do_- Fire-exposed headers in 8- or 12-in. solid walls 930 8 —74. 2 SLP do . _ Fire endurance. _ _ 930 9 —38. 5 SLP . ..do. - __ __do --_ 930 30 -36. 5 SLP - _do. - Fire and water _ 930 6 SLP _ _do_ - Fire endurance 930 9 —34. 9 SLP -.do.. _ . 930 11 -31. 9 SLP _do _ 930 6 -32. 6 SLD do Fire endurance.- 660 20 —86. 6 SLD _do _do __ _ 660 18 -73. 1 SLD do . _ _do_ -_ 700 25 —54. 6 CLM Clay do 760 15 -53. 5 CLM _do Fire-exposed headers in 8- or 12-in. rolok walls. . . . Unexposed stretchers in 12-in. rolok wall

760 15 — IX 9 CLM do 760 6 -a 4 CLM . do __ 760 6 -5. 4 CLI do Fire-exposed stretchers in 8-in. rolok walls . 1, ISO 16 CLI .do Fire-exposed headers in 8-in. rolok walls l. ISO 17 -57. 3 SHW Shale _ 1. 720 15 -77.

SHW do Fire-exposed headers in 8-in. rolok walls 1. 760 14 -34.4 SHW 1, 720 15 +4.9

1 No tests.

2 Fluxed. 49
Some of the loss was due to damage to the

masonry specimen incurred in cutting it out of the wall after test. It might also be noted that

the tests were made with specimens about 2 % ft high, and the effect on strength, such as from loss of header bond in the fire test, would not be as much as with specimens of greater height.

9. Summary and Conclusions 9.1.

Materials of Construction

The bricks included a representative range in

kind and quality and met ASTM specifications

from the standpoint of strength and other properties, for use in interior or exterior walls of buildings (table 1). The portland cement, lime, plaster, and sand

also met recognized acceptance standards. The

mortar strengths (table 2) were somewhat lower

than prescribed for given proportions, apparently

due to the wet mix, the samples being taken from

the mortar prepared by the workmen constructing

the walls.

9.2.

Workmanship

The workmanship for most of the large solid and all-rolok hollow walls was hardly up to the

usual standard for building construction. This

applied particularly to the filling and pointing of mortar joints at the surface of unplastered walls. The strength of the masonry as based on compressive tests of piers (table 5) had a factor of safety of 3 or more on working loads applicable

for given wall designs.

9.3. Wall Constructions

The walls tested were of designs representative

of those in common use, and some new designs were included that as yet have found only limited

application in building construction. They were

subjected to fire test restrained within heavy

panel frames, unrestrained with freedom to

deflect outward at the top, and under applied

working loads. The heights of the large walls were representative of moderate story heights of buildings. Supplementary information was obtained with walls or smaller size.

9.4. Testing Procedure

The furnace fire exposure was controlled according to the present procedure for conduct of fire tests [8], except that, in the earlier tests going

beyond 8 hr, the furnace temperature was raised

above 2,300° F to a maximum of 2,500° F (sec. 4.4(a)). The comparison on severity of furnace

exposure given in tables 9 and 10 was based on

the area under the furnace curve of the present

standard, hence the severity in some of these

earlier tests of long duration appears relatively

high. Otherwise, the furnace control was well

within permitted tolerance limits. In the earlier tests, the method of determining

temperatures on the unexposed surface had not

been standardized, but sufficient information was

obtained in these and later tests to evaluate results

in terms of the present procedure.

The procedure used in some of the fire and hosestream tests differed in only minor details from the

present procedure with respect to the nozzle

pressure and duration of the hose-stream application. Although no load was applied in these

earlier tests, the evidence appears conclusive

(sec. 7.3) that the walls would have sustained the

working load during the test and twice this load

after cooling, if tested according to the present

procedure [8], On other aspects, the test data

indicated that the walls fully met the requirements of the test (sec. 7.1 and 7.2).

9.5.

Conditioning Before Test

For the 4-in. walls and the 8-in. walls of clay or shale bricks, the conditioning procedure used (sec. 3.5) apparently resulted in a degree of dryness

within the range attained by walls within heated

buildings. Concrete and sand-lime bricks are more retentive of moisture, and for them, as well

as for all 12-in. solid walls and 8- and 12-in. plastered walls, the desired degree of dryness may not

have been attained.

A number of the walls were dried to constant

weight at temperatures in the range 160° to 180°

F, and in the general evaluation of the results of the tests, due consideration is given to then- performance in the fire test in comparison with

the results obtained with walls seasoned under room conditions.

9.6.

Fire-Resistance Periods

The main result of this type of fire test is the

time the construction withstands the test under

the given performance limits. The limiting condition may be failure under working load or collapse

from excessive lateral deflection, certain temperature-rise limits reached within the wall or on the

surface not exposed to fire, passage of flame, or

ignition of combustible material in contact on the

unexposed side. Satisfactory performance in the

fire and hose-stream test is also a corollary re- quirement.

The fire-resistance periods are based upon the events during the test while the construction was

exposed to fire. Subsequent occurrences (tables

11 and 12), such as increase in temperature rise on the unexposed side and ignition of pads in contact therewith, are not considered of direct concern. In the fire test, the furnace temperature was at or near maximum at the end of the fire exposure, and the subsequent heat from the

furnace was, in effect, a continuation of the test

of the wall in place at the furnace.

50
Also, high temperatures of fires in buildings are not generally sustained for long periods, and the

cooling periods are longer than those for the test furnace. Thus, in fire severity tests with combustibles burned under representative conditions in buildings, the maximum temperatures were

reached relatively early, but the greater part of the area under the time-temperature curve serving

as a measure of fire severity, was obtained in the

subsequent period.

Accordingly, fire-division walls in buildings

having a fire-resistance equal to the fire severity

to be expected should give protection during both

the active period of the fire and subsequently.

The fire resistance of brick walls is relatively high,

and the thickness required for other reasons will generally give the required fire resistance. However, this is not always the case, particularly

where hot debris remains in contact with the wall. Hence, the possibility that materials on the unex- posed side or combustible members framed into

the wall will ignite after the fire is under control, or even after extinguishment. This is attested by

such occurrences in building fires.

a. Theoretical Relations

For the conditions of the fire test it has been

found that, with constructions of the same material, the time of the limiting temperature rise at points within the wall or on the unexposed surface

varies with the 1.7 power of the thickness of solid

material intervening between these points and the

fire-exposed surface [7], Furthermore, the effect

of plaster and of the air spaces in the construction can be evaluated on a similar basis [9],

Use will be made of these relations only in comparing results with similar walls of different thick- nesses and in appraising results in which the degree

of conditioning or size of wall may have had significant effects.

b. Loading and Stability In the fire tests, the 4- and 8-in. solid and all- rolok walls carried working loads up to or beyond

the time when temperature-rise limits were reached on the unexposed side. For the 10-in. cavity wall, an adjustment in the working load had to be made

before this condition was met. For 12-in. solid

walls of clay bricks having a low softening point

and for those of sand-lime bricks having a compressive strength of less than 2,500 lb/in. 2

, there was failure under load before the limiting temperature rise was reached on the unexposed side. With these exceptions, the walls shown to have

given fire-resistance periods can be considered as able to carry up to these limits the working loads

appropriate for their design, thickness, brick

material, and mortar. There was no collapse in the tests of unloaded

walls because of excessive lateral deflection.

c. Average Fire-Resistant Periods

Fire-resistance periods or limits of brick walls

of solid and hollow designs are given in table 17, as based upon results from the present tests. They

are given to the nearest % hr up to 2 hr, to the

nearest y2 hr in the range from 2 hr to 4 hr, and to the nearest hour above 4 hr. Table 17. Fire-resistance periods of brick walls

Average fire-resistance limit based on—

Wall design Sketchin fig- ure 1

Nominal

thick- ness Brick materia! Plaster Wall or test Time

Time of temperature rise

load can

be sup- ported On un- exposed

surface

4-in in- side un- exposed

surface

Solid A

in.4 Clay and shale

_ __do None -_ ... 1 to 3, 5 to 7, 10A, lOB...

8, 9

hr

1 1M

hrm

hr Do A 4 Both sides _ _ 2h 24

Do_ B 8 _ .do _ . 11 to 24.... 0 Do. B 8 . do 37. .. 3 Do C 12 do.2 None... ... . 43, 44 8 9 Do C 12 38, 39, 41, 42, 45 10 10 - Do B 8 Concrete. _ .do 25' to 28 6 6 2U

Do C 12 . ..do < _ ._ do 46 to 50. 12 12 s Do B 8 Sand-lime. _ ... do 29 to 36 i Do C 12 ..do 51 to 53 9 12 9

All rolok . D 8 54 to 59 24 1 Do ... D 8 60, 61... 4 4 14

All rolok and alt. rolok F, G 24

G

12 do None .. 64; 65... 5 5 Alt. rolok .... 12 do Both sides 66 7 7 34

Cavity L 10 70 to 72.... J 5 5 14 Do L 10 do .. _ do 70 to 72 4 5 5 •2

1 Load limited to 80 lb/in.2

, centrally applied, and with pilasters to 160 lb/in. 2

. Walls to be laid up in mortar comparable to the cement or cement -lime mortars used in this test project, or equivalent in other mortars.

2 Bricks of burned clay and shale having softening point below 2,200° F.

3 Bricks of burned clay and shale having softening point of 2,200° F or over.

3 No cinders or other constituents in the aggregate that lower the softening point of the concrete below 2,800° F.

5 Working load limited to one-third of load allowed for 8-in. solid brick walls of comparable material.

e Based on embedment of ends of combustible members on not less than three sides. 51
The values in table 17 are below the average

result with a group of comparable walls but were

not as low as the minimum in all cases. Further

reductions were made on account of size and degree

of seasoning of the walls. The increase credited for plaster is based upon

coatings of not less than % in. thickness of gypsum

or portland-cement plaster, comparable to those

applied in connection with these tests. For

periods determined by temperature rise on the

unexposed side, the plaster is assumed to be applied on both sides of the wall. Where determined by

bearing capacity or protection of ends of combustible members 4-in. inside the unexposed

surface, the plaster need be applied only on the

fire-exposed side.

( 1 ) Clay- and shale-brick walls of 4-in. thickness. The limit of 1 / hr for the unplastered wall is based upon an average test result for the group

of 1 hr 21 min, the minimum in any test being

1 hr 8 min. Here little or no discount need be

made for size of wall or degree of seasoning. Shalebrick wall 6 and clay-brick wall 2 carried a load

of 80 lb/in. 2 for 1 hr 44 min and 2 hr 20 min,

respectively. The results of tests 10A and 10B

indicate that with pilasters (fig. 2) the load can

be increased to 160 lb/in. 2

(2) Solid clay- and shale-brick walls of 8- and

12-in. thickness. The 5 hr period for unplastered

walls is within the limits determined in the tests with normally seasoned walls. The average limit

of temperature rise in the wall of 2 In- compares

with the average from 12 tests of 2 hr 16 min.

The periods given for plastered walls are lower

than the results with plastered wall 37, both

because of size of wall and degree of dryness.

They are in accord with a conservative inter- pretation of results obtained with plaster and also with theoretical relations [9], Similar considerations were applied in the derivation of periods for the 12-in. walls.

(3) Solid concrete and sand-lime brick walls of

8- and 12-in. thickness. In arriving at the periods

listed in table 17, due consideration was given to the degree of dryness of the walls at the time of

test, and the possible effect of border conditions

for other than the large walls. The periods given

for the walls of 12-in. thickness and those more

fully experimentally determined for the 8-in. walls are in general theoretical accord. The

aggregate for concrete bricks in 12-in. walls should

contain no cinders or other constituents that

unduly lower the fusion point. Allowance was made for the extra width of sand-lime bricks

from source SLD.

(4) 1 Vails of all-rolok and alternate rolok designs.

For the unplastered walls, the limits given in

table 17 are taken at or a little below the average

results from the tests. The periods arrived at for

the plastered walls are below experimental values

that apparently were unduly influenced by degree

of seasoning before test and cooling from the

borders during test.

(5) Cavity walls. Only the cavity wall of nominal 10-in. thickness was included in the tests, and the fire-resistance periods in table 17 are near

the average of the test results.

(6) Walls of other designs. A number of walls

of rolok-bak and rolok-faced designs were included

in the series, and while the results are informative,

they do not form an adequate basis for evaluation

in terms of fire-resistance periods, pending accrual of additional information from further fire tests.

Acknowledgments are made to a number of former members of the Fire Resistance Section of the National Bureau of Standards for conduct of

tests and reducing the large volume of test data

to usable form, among whom mention is here

made of Clement R. Brown, Nolan D. Mitchell,

and Harry E. Newcomer. Acknowledgments are

also made to William Carver, formerly architect

with the Common Brick Manufacturers Association of America, for development of a number of the hollow wall designs, and to C. 0. Christianson,

Research Associate with the Association, for as- sistance on fire tests of the walls.

10. References

[1] S. H. Ingberg and H. D. Foster, Fire resistance of hollow load-bearing wall tile, BS J. Research 2, 27

(1929) RP37.

[2] S. H. Ingberg and Nolan D. Mitchell, Fire tests of wood- and metal-framed partitions, NBS Building

Materials and Structures Report BMS71 (1941).

[3] Harry D. Foster, Earl R. Pinkston, and S. H. Ingberg,

Fire resistance of walls of lightweight-aggregate concrete masonry units, NBS Building Materials and

Structures Report BMS117 (1950).

[4] Harry D. Foster, Earl R. Pinkston, and S. H. Ingberg,

Fire resistance of walls of gravel-aggregate concrete masonry units, NBS Building Materials and Structures Report BMS120 (1951).

[5] S. H. Ingberg, H. K. Griffin, W. C. Robinson, and

R. E. Wilson, Fire tests of building columns, BS

Tech. Pap. T184, p. 99-106 (1921).

[6] Standard specifications for fire tests of building construction and materials, American Society for Testing Materials Designation Cl 9-33 or American

Standards Association No. A2-1934.

[7] S. H. Ingberg, Size and border conditions of test speci- mens in their relation to results of fire tests, Am.

Soc. Testing Materials Proc. 49, p. 1065-77 (1949).

[8] Standard methods of fire tests of building construction and materials, American Society for Testing Materials Designation El 19-50.

[9] Fire-resistance classifications of building constructions,

NBS Building Materials and Structures Report

BMS92, Appendix B (1942). Washington, April 19, 1954.

o

52
BUILDING MATERIALS AND STRUCTURE REPORTS

[Continued from cover page n]

BMS32 Structural Properties of Two Brick-Concrete-Block Wall Constructions and a Concrete- Block Wall Construction Sponsored by the National Concrete Masonry Association. * BMS33 Plastic Calking Materials * BMS34 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 1 15£ BMS35 Stability of Sheathing Papers as Determined by Accelerated Aging * BMS36 Structural Properties of Wood-Frame Wall, Partition, Floor, and Roof Constructions

With ‘Red Stripe” Lath Sponsored by The Weston Paper and Manufacturing Co.. 10£ BMS37 Structural Properties of “Palisade Homes” Constructions for Walls, Partitions, and

Floors, Sponsored by Palisade Homes * BMS38 Structural Properties of Two “Dunstone” Wall Constructions Sponsored by the W. E. Dunn Manufacturing Co 10i BMS39 Structural Properties of a Wall Construction of “Pfeifer Units” Sponsored by the Wisconsin Units Co 10(4 BMS40 Structural Properties of a Wall Construction of “Knap Concrete Wall Units” Sponsored

by Knap America, Inc * BMS41 Effect of Heating and Cooling on the Permeability of Masonry Walls * BMS42 Structural Properties of Wood-Frame Wall and Partition Construction with “Celotex”

Insulating Boards Sponsored by The Celotex Corporation * BMS43 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 2 * BMS44 Surface Treatment of Steel Prior to Painting * BMS45 Air Infiltration Through Windows 20(4 BMS46 Structural Properties of “Scott-Bilt” Prefabricated Sheet-Steel Construction for Walls,

Floors, and Roofs Sponsored by The Globe-Wernicke Co * BMS47 Structural Properties of Prefabricated Wood-Frame Constructions for Walls, Partitions, and Floors Sponsored by A.merican Houses, Inc 20(4 BMS48 Structural Properties of “Precision-Built” Frame Wall and Partition Constructions

Sponsored by the Homasote Co * BMS49 Metallic Roofing for Low-Cost House Construction 25£ BMS50 Stability of Fiber Building Boards as Determined by Accelerated Aging * BMS51 Structural Properties of “Tilecrete Type A” Floor Construction Sponsored by the

Tilecrete Co * BMS52 Effect of Ceiling Insulation Upon Summer Comfort 15(4 BMS53 Structural Properties of a Masonry Wall Construction of “Munlock Dry Wall Brick”

Sponsored by the Munlock Engineering Co 10£ BMS54 Effect of Soot on the Rating of an Oil-Fired Heating Boiler 10(4 BMS55 Effects of Wetting and Drying on the Permeability of Masonry Walls * BMS56 A Survey of Humidities in Residences 10(4 BMS57 Roofing in the United States—Results of a Questionnaire * BMS58 Strength of Soft-Soldered Joints in Copper Tubing 15(4 BMS59 Properties of Adhesives for Floor Coverings * BMS60 Strength, Absorption, and Resistance to Laboratory Freezing and Thawing of Building

Bricks Produced in the United States 30(4 BMS61 Structural Properties of Two Nonreinforced Monolithic Concrete Wall Constructions.. * BMS62 Structural Properties of a Precast Joist Concrete Floor Construction Sponsored by the Portland Cement Association 15(4 BMS63 Moisture Condensation in Building Walls * BMS64 Solar Heating of Various Surfaces 10(4 BMS65 Methods of Estimating Loads in Plumbing Systems 20(4 BMS66 Plumbing Manual 40(4 BMS67 Structural Properties of “Mu-Steel” Prefabricated Sheet-Steel Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by Herman A. Mugler 20(4 BMS68 Performance Test for Floor Coverings for Use in Low-Cost Housing: Part 3 25(4 BMS69 Stability of Fiber Sheathing Boards as Determined by Accelerated Aging 10(4 BMS70 Asphalt-Prepared Roll Roofings and Shingles 20<4 BMS71 Fire Tests of Wood- and Metal-Framed Partitions 30(5 BMS72 Structural Properties of “Precision-Built, Jr.” Prefabricated Wood-Frame Wall Construction Sponsored by the Homasote Co * BMS73 Indentation Characteristics of Floor Coverings 10(5 BMS74 Structural and Heat-Transfer Properties of “U. S. S. Panelbilt” Prefabricated SheetSteel Constructions for Walls, Partitions, and Roofs Sponsored by the Tennessee

Coal, Iron & Railroad Co 206 BMS75 Survey of Roofing Materials in the North Central States 156 BMS76 Effect of Outdoor Exposure on the Water Permeability of Masonry Walls * BMS77 Properties and Performance of Fiber Tile Boards

BMS78 Structural, Heat-Transfer, and Water-Permeability Properties of Five Earth-Wall

Constructions 35c

BMS79 Water-Distributing Systems for Buildings 206

BMS80 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 4 BMS81 Field Inspectors’ Check List for Building Constructions (cloth cover, 5 x 7h inches).. 35c BMS82 Water Permeability of Walls Built of Masonry Units 25c

BMS83 Strength of Sleeve Joints in Copper Tubing Made With Various Lead-Base Solders 15c BMS84 Survey of Roofing Materials in the South Central States *

* Out of print. [List continued on cover page iv]
BUILDING MATERIALS AND STRUCTURE REPORTS

[Continued from cover page in] BMS85 Dimensional Changes of Floor Coverings With Changes in Relative Humidity and

Temperature * BMS86 Structural, Heat-Transfer, and Water-Permeability Properties of “Speedbrik” Wall

Construction Sponsored by the General Shale Products Corporation 150 BMS87 A Method for Developing Specifications for Building Construction—Report of Subcommittee on Specifications of the Central Housing Committee on Research,

Design, and Construction 200 BMS88 Recommended Building Code Requirements for New Dwelling Construction With

Special Reference to War Housing -j- BMS89 Structural Properties of “Precision-Built, Jr.” (Second Construction) Prefabricated Wood-Frame Wall Construction Sponsored by the Homasote Co 150 BMS90 Structural Properties of “PHC” Prefabricated Wood-Frame Constructions for Walls,

Floors, and Roofs Sponsored by the PHC Housing Corporation 150 BMS91 A Glossary of Housing Terms * BMS92 Fire-Resistance Classifications of Building Constructions 350 BMS93 Accumulation of Moisture in Walls of Frame Construction During Winter Exposure. _ * BMS94 Water Permeability and Weathering Resistance of Stucco-Faced, Gunite-Faced, and

“Knap Concrete-Unit” Walls * BMS95 Tests of Cement-Water Paints and Other Waterproofings for Unit-Masonry Walls 250 BMS96 Properties of a Porous Concrete of Cement and Uniform-Sized Gravel 100 BMS97 Experimental Dry-Wall Construction With Fiber Insulating Board * BMS98 Physical Properties of Terazzo Aggregates * BMS99 Structural and Heat-Transfer Properties of “Multiple Box-Girder Plywood Panels” for Walls, Floors, and Roofs * BMS100 Relative Slipperiness of Floor and Deck Surfaces * BMS101 Strength and Resistance to Corrosion of Ties for Cavity Walls * BMS102 Painting Steel 150 BMSI 03 Measurements of Heat Losses From Slab Floors * BMS104 Structural Properties of Prefabricated Plywood Lightweight Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by the Douglas Fir Plywood Association.. * BMS105 Paint Manual with particular reference to Federal Specifications $1. 50 BMS106 Laboratory Observations of Condensation in Wall Specimens 100 BMS107 Building Code Requirements for New Dwelling Construction * BMS108 Temperature Distribution in a Test Bungalow With Various Heating Devices 150 BMS109 Strength of Houses: Application of Engineering Principles to Structural Design $1. 75 BMS110 Paints for Exterior Masonry Walls 200 BMSlll Performance of a Coal-Fired Boiler Converted to Oil 150 BMS112 Properties of Some Lightweight-Aggregate Concretes With and Without an Air- Entraining Admixture 150 BMS113 Fire Resistance of Structural Clay Tile Partitions 150 B MSI 14 Temperature in a Test Bungalow With Some Radiant and Jacketed Space Heaters 250 BMS115 A Study of a Baseboard Convector Heating System in a Test Bungalow 200 BMS116 Preparation and Revision of Building Codes 200 BMS117 Fire Resistance of Walls of Lightweight Aggregate Concrete Masonry Units 250 BMS118 Stack Venting of Plumbing Fixtures 250 BMS119 Wet Venting of Plumbing Fixtures 250 BMS120 Fire Resistance of Walls of Gravel-Aggregate Concrete Masonry Units 150 BMS121 Investigation of Failures of White-Coat Plasters 300 BMS122 Physical Properties of Some Samples of Asbestos-Cement Siding 200 BMS123 Fire Tests of Wood-Framed Walls and Partitions With Asbestos-Cement Facings 150 BMS124 Fire Tests of Steel Columns Protected With Siliceous Aggregate Concrete 150 BMS125 Stone Exposure Test Wall 300 BMS126 The Self-Siphonage of Fixture Traps 200 BMS127 Effect of Aging on the Soundness of Regularly Hydrated Dolomitic Lime Putties 150 BMS128 Atmospheric Exposure Tests of Nailed Sheet Metal Building Materials 200 BMS129 Fire Endurance of Shutters for Moving-Stairway Openings 100 BMS130 Methods and Equipment for Testing Printed-Enamel Felt-Base Floor Covering 150 BMS131 Fire Tests of Gunite Slabs and Partitions 150 BMS132 Capacities of Plumbing Stacks in Buildings 250 BMS133 Live Loads on Floors in Buildings 250 BMS134 Fire Resistance of Concrete Floors * BMS135 Fire Tests of Steel Columns Encased With Gypsum Lath and Plaster 150 BMS136 Properties of Cavity Walls 150 BMS137 Influence of the Wash From Bronze on the Weathering of Marble 150 BMS138 Effect of Edge Insulation Upon Temperature and Condensation on Concrete-Slab

Floors 200 BMS139 Studies of Stone-Setting Mortars 250 BMS140 Selected Bibliography on Building Construction and Maintenance 300 BMS141 Fire Endurance of Open-Web Steel-Joist Floors With Concrete Slabs and Gypsum

Ceilings 200 BMS142 Frost Closure of Roof Vents 250 BMS143 Fire Tests of Brick Walls 350

* Out of print. fSuperseded by BMS107.