NATIONAL BUREAU OF STANDARDS REPORT

5428

VOLUME- CHANGE TESTB OP MASONRY MATERIALS

USED AT CHINCOTEAGUE NAVAL AIR STATION

by

L. E„ Cattaneo and D„ Watstein

Report to

Bureau of Yards and Docks

Department of the Navy

U. S. DEPARTMENT OF COMMERCE

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THE NATIONAL BUREAU OF STANDARDS

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NATIONAL BUREAU OF STANDARDS REPORT

NBS PROJECT

1001-30-4810 June 28, 1957

NBS REPORT

5428

VOLUME-CHANGE TESTS OF MASONRY MATERIALS

USED AT CHINCOTEAGUE NAVAL AIR STATION

by

L. E. Cattaneo and D. Watstein

To

Bureau of Yards and Docks

Department of the Navy

IMPORTANT NOTICE

NATIONAL BUREAU OF STAN

intended for use within the Go

to additional evaluation and rev

listing of this Report, either in the Office of the Director, Natic however, by the Government ag

to reproduce additional copies

Approved for public release by the

Director of the National Institute of

Standards and Technology (NIST)

on October 9, 201 5.

gross accounting documents

ally published it is subjected

production, or open-literature

n is obtained in writing from

.ich permission is not needed,

epared if that agency wishes

<NBS>

U. S. DEPARTMENT OF COMMERCE

NATIONAL BUREAU OF STANDARDS

VOLUME -CHANGE TESTS OF MASONRY MATERIALS

USED AT CHINCOTEAGUE NAVAL AIR STATION

by

L. E. Cattaneo and D. Watstein

Abstract

In order to determine the cause of severe

cracking in brick walls at Chincoteague

Naval Air Station, laboratory specimens

of brick masonry were constructed of materials from the same source as those used

in original walls which exhibited cracking.

Specimens of masonry and of component materials were observed for volume changes

caused by moisture content variation induced

by normal curing and by cyclic soaking and

drying. Mortar specimens exhibited ordinary

contraction and expansion with drying and

soaking. Slight expansions were observed in

masonry and brick specimens during certain

drying periods. Results are discussed and

presented in graphic and tabular form.

1. INTRODUCTION

During construction of an infirmary building at Naval

Air Station, Chincoteague, Virginia, under Contract NOy 91316,

it was observed that severe cracking had occurred in certain

areas of the brick-faced cast concrete foundation walls. In

order to obtain data which might help determine the cause of

such cracking, samples of the masonry materials were submitted

to the National Bureau of Standards for testing.

Photographs on file at the Bureau of Yards and Docks unde

Code D-231 show that cracks developed both in the concrete

foundation and in the mortar joints of its brick facing. The

cracks had an appearance which indicated a relative movement

between concrete and masonry that could be attributed to exces

sive shrinkage of the concrete or excessive expansion of the

masonry. Since this observation pointed to volume change as
*

.
2 . the property of major interest it was planned to investigate

the effect of moisture on various combinations of the materials submitted.

2. SPECIMENS AND TESTS

The samples received from the Naval Air Station Public

Works Office at Chinco teague , Virginia, consisted of one bag

of masonry cement, three cu ft of masonry sand, and 130 cored

clay facing brick. These materials were used to prepare the

volume- change specimens listed in Table 1 which shows their

designation and treatment.

Brick wall specimens and accompanying mortar specimens

were made for long term observation of volume change during

air- curing after construction. Small 3- course masonry assemblages and additional mortar specimens were made for observation of volume change caused by oven-drying. Individual

brick specimens were prepared for observation of volume change

caused by soaking followed by (l) normal drying, ( 2 ) ovendrying, and (3) autoclaving. These tests consumed a period of

102 days designated as Phase I. During an additional period

of 63 days, designated as Phase II, all specimens were observed

for volume change caused by cyclic soaking and drying. Tests

were begun on November 8 , 1956, and were terminated on April

22, 1957.

Table 1. Schedule of Test Specimens

T S

6 Des

f of specimen

igna tion

specimen Treatment (by days)

(---End of Phase I)

Wall W-l Fabricated; air-dried 102. Ovendried 7 , immersed 7 ; air dried l\2 .

Wall W-2 Fabricated; air-dried 102. Immersed

7 ; air-dried 21 ; immersed 7 ; airdried 28 . Wall W-3 Fabricated; air-dried 102. Immersed

7 ; oven-dried 7 > air-dried 42 .

3 - course

assemblage

A-l Fabri cated;moist- cured 28, air-dried

7 ; oven-dried 5 ; air-dried 62 . Oven-dried 7; immersed 7; air-dried 42
’

.
3

Table 1. Schedule of Test Specimens (continued)

Type

of

specimen

Designation

of specimen Treatment (by days)

(-:'-End of Phase I)

3

“ course

as semblage

A2

Fabricated; moist-cured 28; air-dried 7;

oven-dried 3; air-dried 62. Immersed 7

air-dried 21 ; immersed 7 ; air-dried 28 .

3 - course

as semblage

A3

Fabricated; moist-cured 28; air-dried 7;

oven-dried 3; air-dried 62. Immersed 7

oven-dried 7 ; air-dried 1|2 . Mortar M-l Molded; treatment same as for W-l.

Mortar M-2 Molded; treatment same as for ¥-2.

Mortar M-3 Molded; treatment same as for W-3»

Mortar M-i| Molded; treatment same as for A-l

Mortar M-3 Molded; moist-cured 28; air-dried 7,' oven-dried 3 ; air-dried 9 ; therm. coeff.

determ, and autoclav. test 21 ; ovendried 7 ; air-dried 23 .

•”*

Mortar M-6 Molded; treatment same as for A-3

Bri ck B-10 Immersed 3; air-dried 10; oven-dried 3;

air-dried 62 . Oven-dried 7; immersed

7 ; air-dried \\2.

Brick B-20 Immersed 3; air-dried 10; oven-dried 3;

air-dried 23 ; autoclav. test 7 ; ovendried 7; air-dried 23. *”* Oven-dried 7;

immersed 7 ; air-dried \\2.

Bri ck B- 30 Immersed 1; air-dried 9; oven-dried 3;

air-dried 9 ; thermal coeff. determ, and

autoclav. test 21 ; oven-dried 7 ; airdried 23. Immersed 7; oven-dried 7;

air-dried \\2.

Bri ck B-40 Immersed 1; air-dried 9; oven-dried 3;

air-dried 62. Immersed 7; oven-dried

7 ; air-dried I4

. 2 .

4 .

3. MATERIALS

3.1 Cement

One bag of North American Corporation Blue Bond Masonry

Cement which had been in storage at the construction site since

August 10, 1956, was received on October 29, 1956, and stored

In a dry laboratory. The cement was found to contain lumps as

large as 1 inch. Sieving through a #8 mesh sieve eliminated

approximately 10 percent of the cement sample. Testing of the

cement for flow after suction, autoclave expansion and time of

setting showed that it complied with the requirements stated

in ASTM Specification C91-55T . (See Table 2).

Table 2. Physical Properties of Cement

Flow after suction, %

Autoclave expansion, %

Time of setting

82

0.08

Satisfactory

3.2 Sand

The masonry sand submitted was received and maintained in

a damp, approximately saturated surface-dry condition. Sieve

analysis of the sand performed in accordance with ASTM Specifications C136-l|6 and C117-49 provided the data given in Table 3.

Table 3. Sieve Analysis of Sand

Sieve No.

4

8

16

30

50

100

200

% Passing

(by weight)

100

100

100

92

54

7

0.7
,4 .
5 .

3.3 Brick

Clay bricks used in the tests were manufactured by the

Roanoke Webster Company at Suffolk, Virginia. Each brick contained 3 cores 1 in. in diam and had average dimensions of

7.90- by 3*65- By 2.25 in. When laid the bricks were damp,

having been hosed and allowed to drain in the laboratory for

about 20 hours. Physical properties of the bricks determined

in accordance with ASTM Specification C67-50 are given in

Table 4*

Table 4* Physical Properties of Cored Clay Brick

!

t

i Dry

? weight

i lb/bri ck

i

T

t

4-36

Initial rate

of absorption

gr/brick/min

As laid

9.1

dry

10.6

Absorption

percent

24-hr

cold

5.7

5-hr

boil

8.7

Saturation

coefficient

0 . 64

Modulus

of

rup ture

psi

947

Comp re s- sive

strength

psi

15,980

4. FABRICATION OF SPECIMENS

4.1 Masonry cement mortar

Mortar was hand-mixed and consisted of 1 part cement and

3.7 parts damp sand, by weight; this is equivalent to approximately 1 part cement and 3 parts sand, by volume. The amount

of water added was adjusted to the satisfaction of the mason

and was about 13 percent by weight of the dry materials. The

water- cement ratio was 0.6 by weight, or 0.7 by volume. All

specimens of mortar and of masonry construction were fabricated using one batch of mortar without retempering.

Three 2-in. mortar cubes were molded and moist-cured for

24 hr before being removed from the molds and immersed in

water for 27 days. The average compressive strength of the

mortar cubes in a saturated surface-dry condition at 28 days

was 1020 psi.
.

.
6 . Six prismatic volume- change specimens of mortar measuring

1- by 1- by 11-in. were cast in steel molds which provided for

the embedment of spherical contact reference points in the ends,

(See Pig, 1). Molds were designed so that the distance between

the innermost ends of the reference inserts (used as the gage

length in computations of unit length change) was 10 ± 0.1 in.

( cf

.

ASTM Specification C157-54T). After mortar specimens M-l,

M-2, M-3, were air-cured in the molds for 24 hr, they were removed from the molds and exposed to free circulation of laboratory air. Mortar specimens M-4, M-5>, M-6, were moist- cured in

the molds for 24 hr, then removed, and subjected to immersion

curing for an additional 27 days.

4.2

Brick specimens

Pour volume- change specimens were prepared by cementing

brass gage plugs into pairs of holes in each of two opposite

faces of whole bricks (cf. ASTM Specification C34l“S4T). After

moist curing of the portiand cement paste in the gage plug

holes, a 0 . 04-in. diam reference hole was drilled in each plug

to provide a 5-in. gage length on each brick face. (See Pig.l).

4.3

3-Conrse assemblages

Three small volume-change specimens of brick masonry construction, approximately 8 in. high and 16 in. long, were fabricated for ease of handling in performing accelerated ovendrying tests. These contained 3-courses of two bricks each and

three beds of mortar approximately l/2 in. thick. (See Pig. l)

.

Spherical contact reference points were cemented in the ends

of the six sawed half-bricks in the middle courses before laying, The distance between the inner-most ends of the reference

inserts (used as the gage length) was 14-5 - 0.1 in. These

specimens were air-cured for 24 hr and cured by immersion for

27 days.

4.4

Wall specimens

Three brick walls approximately 2 feet square and one

wythe thick were constructed for volume change observation under

laboratory conditions. Each of these contained nine courses of

three bricks each with horizontal and vertical mortar joints

approximately 1/2 in. thick. Before construction, brass plugs

were cemented in holes drilled in one face of the necessary

whole or sawed half-bricks which, when laid, positioned the

plugs as shown in figure 2. Twenty-four hours after fabrication of the walls a 0.04 in. diam reference hole was drilled in
'
7.

each brass plug so that any vertical or horizontal pair of

reference holes determined a 20-in. gage length. Walls were

constructed on 1 /ip— by 2- by 4~in. steel bearing plates resting on l/2- by 4“ in. steel rollers to minimize resistance to

movement caused by shrinkage or expansion.

4.5 Joints

All bed and vertical joints in specimens of masonry construction were approximately l/2 in. thick and were made full.

Mortar for bed joints was troweled on and furrowed; mortar

for end joints was buttered on edges. Desired joint thickness

was obtained by tamping brick and extruding excess mortar.

Joints were cut flush with the face of the wall and left untooled. At conclusion of tests, examination of joint interiors in wall specimen W-3 confirmed existance of solid joints.

5. MEASURING APPARATUS

5.1 Balances

One of three balances was used to weigh each of the various specimens to determine moisture content. Choice of balance

was governed by proximity of its maximum capacity to weight of

specimen. All balances were sensitive to within 0.2 percent

or less of the weight of the lightest specimen weighed on them.

Mortar specimens and brick specimens were weighed to the

nearest 0.5 gram, 3-course assemblages to the nearest 5 grams,

and walls to the nearest 0.1 lb.

5.2 Extensome ters

Determinations of change in linear dimensions were made

with one of four extensome ters , all equipped with 0.0001-in.

micrometer dials. Mortar specimens having a gage length of

10 ± 0.1 in. were measured with a dial micrometer of the type

suggested in ASTM Specification Cl57-54'i* Brick specimens

having a gage length of 5 in. were measured with a 5- in.

Whittemore strain gage. Small 3-course assemblages having a gage length of 14*5 ±0.1 in. were measured with the dial

micrometer shown in figure 2. Wall specimens having 20-in.

gage lengths were measured with a 20-in. Whittemore strain

gage. Readings made with all extensome ters were estimated

to the nearest 0.1 dial graduation and were referred to appropriate Invar standard bar datum readings. Extensome ter readings were repeated to obtain a value reproducible within 0.5

dial graduation.

8 .

6. PROCEDURE

Fabrication, air-drying, immersion, and observation of

specimens took place in a laboratory in which the temperature

was normally 72° - 2° F. However, length change determinations were corrected to 72° F for thermal movement caused by

exceptional temperature variations. The coefficient of

linear thermal expansion used for this nurpose was determined

brick, separately. Variations in laboratory relative humidity

were recorded for comparison with corresponding length change

data. All oven-drying was done at temperatures between 230 F

and 239° F.

Tests were conducted in two phases. During the first

period of approximately three months (Phase I) wall specimens

were permitted to air-dry undisturbed, being observed for

length changes only. All other specimens were observed at

intervals for length and weight changes during this period.

Analysis of data accumulated during the first three months

suggested the need for extended observations of the walls subjected to further tests. During this second period of about

two months (Phase II) both length and weight changes were deter

mined for all specimens.

6.1.1 Wall specimens W-l, W-2. W-3 and

mortar specimens M-l, M-2, M-3

The treatments of wall and mortar specimens bearing the

same identification number were identical. Initial gage length

were determined after the first Zl[ hr of curing in laboratory

air and were used as bases for all subsequent length changes.

Specimens were measured at progressively longer intervals over

a total air-drying period of 102 days.

Gage lengths of all six specimens measured at the age of

28 days in a saturated surface dry condition (after 27 days

experimentally and found F for both mortar and

6.1 Phase I

6.1.2 Assemblages A-l, A-2, A- 3 and

mortar specimens M— Ip , M-5, M-6

9.

immersion curing) were used as bases for subsequent length

changes, 1/

Specimens A-l, A-2, A-3, M-4? and M-6 were then air-dried

for 7 bays, oven-dried for 7 days, and air-dried for an additional 62 days.

Similar treatment of mortar specimen M-5 was interrupted

during the 62 day period for determination of its coefficient

of linear thermal expansion, and autoclave expansion. 2/ The

62 days period for M-5 comprised 9 days of air-drying, 21 days

of handling for thermal and autoclave expansion determinations,

and 7 days of oven-drying followed by 25 days of air-drying.

Specimen M-5 was discarded at the end of Phase I.

6.1.3 Brick specimens B-10, B-20, B-30, B-1|0

Measurements of all brick specimens were begun 25 days

after fabrication of masonry and mortar specimens.

The gage lengths of B-10 and B-20 which were used as

bases for subsequent length changes were measured after 5 days

immersion. Both specimens were then air-dried for 10 days,

and oven-dried for 5 days. B-10 continued to air-dry for 62

additional days while B-20 /Underwent 23 days air-drying, 7 days

handling for auto claving ,£/ 7 days oven-drying and 25 days airdrying {totalling 62 days)

.

Base gage lengths of prepared specimens B-30 and B— lj.0 were

measured in an "as received" condition prior to 2

4

hr immersion.

Both were then air-dried 9 days and oven-dried 5 days. While

B-1|0 continued to air-dry for 62 days, B-30 received 9 days

air-drying, 21 days handling for thermal and autoclave expansion determinations, 7 days oven-drying and 25 days air-drying

(totalling 62 days).

l/ Measurements of mortar specimens M~4? M-5? M-6 at the age of

2

4

hr made possible a calculation of their average expansion

(.012$) after 27 days of immersion curing (see Pig. 6). The

heavier weight of the assemblages A-l, A-2, A-3? and the

method used to measure them (see Pig. 1) made handling at such

an early age for comparable measurements seem inadvisable.

2/ Autoclaving procedure used is described in ASTM Specification

C151-54*
,* .
10 .

6 .

2

Ph a s e II

At the end of Phase I, specimens were subjected to additional cyclic treatment in three groups containing specimens

of various types and were measured intermittently for length

and weight changes.

6.2.1 Group 1

Wall W-l, assemblage A-l, mortar specimens M-l, M-4? and

bricks B-10, B-20, were oven-dried 7 days, immersed 7 days,

and air-dried l\.2 days.

6.2.2 Group 2

Wall W-2, assemblage A-2, and mortar specimen M-2 were

immersed 7 days, air-dried 21 days, immersed 7 days, and airdried 28 days.

tf 6.2.3 Group 3

Wall W-3, assemblage A-3, mortar specimens M~3> M-6, and

bricks B-30, B— IpO were immersed 7 days, oven-dried 7 days and

air-dried \\2 days.

7. RESULTS

7.1 Graphs and Tables

Test results of Phase I are recorded in figures 3* 4? 54

6, 7, and Table 54 test results of Phase II are recorded in

figures 8, 9, 10, and Table 6. Graphs show the results of observations made during the entire test period while Tables 5

and 6 present values of special Interest.

Tabular values of length changes calculated to the nearest

0.001 percent, and of moisture contents to the nearest 0.1 percent are consistent with the sensitivities of the instruments

used to determine them. Length change tabulated as 0, corresponds to a length measurement used as reference for subsequent

readings. Degree of saturation tabulated as 0, indicates the

first determination of the oven-dry weight (in case of repeated

soaking and drying) ; the percentage of saturation tabulated as

100.0, Indicates the first determination of saturated, surfacedry weight.

11 . Values were calculated as follows:

% length change =

100 x (observed gage length) - (initial gage length)

(initial gage length)

rfo saturation =

(observed weight) - (first oven-dry weight)

(first saturated surface-dry weight)- ( first oven-dry weight)

% absorption =

_! nn ^(first saturated surface-dry weight) -( first oven-dry weight)

(first oven-dry weight)

Positive length changes represent expansion and negative ones,

contraction.

7.2 Results of Phase I

Comparison of relative humidities with corresponding length

changes is shown graphically in figures 3 through 7.

(a) Walls W-l, W-2, W-3, showed a tendency to expand

slightly during initial air- curing. Although movement was more

apparent in a vertical direction after 15 days, neither horizontal nor vertical expansion exceeded 0.007 percent in 84 days.

(See Pig. 3 , Table 4). The difference between the amounts of

vertical and horizontal expansions might suggest some relationship to the number of joints included by respective gage lengths.

(b) Mortar specimens M-l, M-2, M-3? which accompanied the

walls showed a rapid contraction in the first 6 days which almost

equalled their maximum shrinkage of 0.065 percent developed in

70 days. (See Pig. 4? Table 5). However, it should be noted that

other investigators 3/ have reported that the shrinkage of mortar

3/ R.E. Davis and G.E.Troxell, "Volumetric Changes in Portland

Cement Mortars and Concretes," Proceedings, Am. Concrete Inst.

Vol. 25* 1929, and P . 0 . Anderegg , "Some Properties of Mortar In

Masonry," Proceedings, Am. Soc. Testing Materials, Vol „ 40 , 1940

»
,•

.
12 . specimens cast in non-absorbent molds exceeds considerably that

of mortars left in absorbent molds or between bricks. Furthermore, the contrast between the greater rigidity of brick and

that of mortar joints (when comparing both their moduli and

cross-sectional areas) readily suggests a reason for the apparent ineffectiveness of shrinking mortar in counteracting expansion of adjoining brick.

(c) Assemblages A-l, A-2, A-3, when oven-dried, exhibited

an expansion of 0.014 percent over their saturated condition.

This increased to 0.019 percent after 4^ days of air-drying.

(See Fig. 5> Table 5). In view of the behavior of the separate

mortar and brick specimens, (see figures 6, 7 , and Table 5) > such expansion of assemblages might be attributed to thermal

cracks developed during oven-drying which fail to close entirely

upon cooling. Cracks within the specimen who® widths totalled

0.002 in. in a specimen gage length of 14.5 in. could account

for an apparent expansion of 0.014 percent. The additional

0.005 percent expansion which developed in the assemblages

during subsequent air exposure is in good agreement with the

expansion exhibited by separate mortar and brick specimens exposed to the atmosphere after oven-drying during the same period.

(d) Mortar specimens M-4? M-5> M-6, which accompanied the

3

1- course assemblages contracted 0.159 percent with the aid of

oven-drying. M-4 and M-6 developed an average contraction of

0.l4l percent at equilibrium during subsequent exposure to

laboratory air. (See Fig. 6, Table 5)- M-5> when autoclaved,

showed an expansion of 0.087 percent, (cf. autoclave expansion

of masonry cement, 0.08 percent. Table 2).

(e) All brick specimens showed slight expansion during airdrying after soaking, and during air exposure after oven-drying.

Bricks B-10 and B-20 when soaked for 5 days contracted less

with oven-drying than did B-30 and B-40 which had soaked for

only 1 day. (See Fig. 7? Table 5)- However, It should be noted

that B-30 and B-40 exhibited greater absorption in a shorter

soaking period. Average autoclave expansion of B-10 and B-20

was about 0.08 percent. (See Table 5)
,* .
13.

7.3 Results of Phase II

Since the primary purpose of Phase II was to observe how

length change was affected by extreme moisture content conditions produced in different sequences, relative humidity

variation was considered irrelevant and was not plotted in

the graphical presentation of data. Values of moisture content which corresponded to significant length changes are given

in Table 6. The following limited comments are added to the

results presented In figures 8, 9, and 10, for different

sequences of soaking, oven-drying, and air-drying.

7.3.1 Groups 1 and 3 (Figures 8, 10, Table 6)

(a) Oven-drying of walls ¥-1 and W-3 produced apparent

expansion,, This behavior resembled that of assemblages A-l,

A-2, and A-3? when oven-dried during Phase I. Cracks which

were visible in these two walls during oven-drying were no

longer discernible after cooling. The amount by which vertical movement exceeded horizontal movement was especially notice

able for oven-drying periods indicating a possible joint

separation phenomenon. Expansion continued during air-exposure

which followed either soaking or oven-drying.

(b) Assemblages A-l and A~3 contracted with oven-drying

and expanded with soaking regardless of sequence. Expansion

was exhibited by both specimens during air-exposure after ovendrying or after soaking.

(c) All mortar specimens subjected to soaking and drying

In either order developed more contraction than was observed

during Phase I.

(d) Autoclaved bricks B-20 and B-30 showed greater contrac

tion by oven-drying than non-auto c'laved bricks B-10 and B-1|0„

Expansion occurred during soaking and final air-drying for all

bri cks

.

7.3.2 Group 2 (Pig. 9, Table 6)

(a) Repeated soaking and air-drying of wall W-2 and assemblage A-2 resulted In additional expansion each time.

(b) Mortar specimen M-2 showed expansion by soaking and

additional contraction for each drying.
.

‘
14 .

(c) Moisture contents of W-2 and M-2 (Table 6) are necessarily approximate, having been referred to estimated ovendry weights based on measured properties of similar specimens.

8. SUMMARY AND COMMENTS

During the air-drying period following their construction, brick wall specimens expanded less than 0.01 percent

and maintained this condition for the three months during

which they were observed. Mortar specimens gave no indication of contributing to such expansion whereas brick specimens

exhibited slight expansion during air-drying after soaking and

a very substantial moisture expansion (0.078$) during autoclaving. Additional soaking and drying of the masonry and material

specimens in various ways indicated that oven-drying of jointed

masonry specimens might be too severe a method for determining

their volume change characteristics because of the possibility

of developing thermal cracks.

In attempting to correlate specimen behavior with that of

the original walls in which cracking was first observed it is

to be noted that the horizontal expansion exhibited by wall

specimens ( 0 . 004$)* when applied to 100 ft of wall, would account for an Increase in length or a crack width of only about

0.05 In. However, alternate soaking and exposure to air as

were used In testing specimens of Group 2, Phase II, produced

length changes of 0.023 to 0.037 percent (see figure 9); these

length changes would produce a horizontal movement of 0.28 to

0.44 in. in a wall. 100 ft long and might easily account for the

severe cracking observed in the brick walls at Chincoteague

Naval Air Station. At the same time, It should be remembered

that any such relative movements or separations might be augmented by the shrinkage of a supporting concrete foundation.

The expansion of both the wall specimen and assemblage

(¥-2 and A-2) resulting from alternate wetting and exposure to

air suggests that individual brick specimens should exhibit

similar behavior. This behavior was indeed observed in two

brick specimens (B-10 and B-20) which showed an expansion

following both a period of soaking and during a lengthy period

of drying in laboratory air. While the expansion of Individual

brick was less than that of the wall and assemblage, it is believed that the length changes in both cases could be attributed

to moisture expansion of the clay body of the brick. It will be

recalled that the average moisture expansion of two samples of

brick (B-20 and B-30) when autoclaved for 3 Mr at 295 psi was

0.078 percent.
'* '
15 . The somewhat greater vertical movement observed in brick

wall specimens (see figure 9) may be attributed to the greater

number of joints in that direction and the possibly greater

number of invisible interface separations along horizontal

joints

.

Table 5* Results of Phase I

Walls W-l, W-2, W-3

'Time, days a

/

i

t 1 1 15 1 84 1 102

J Avg'. horiz.

length change. %

!

»

f

0

( base

)

, +0 . 00i|

f 1+0.005t 1+0.002

t

t

t Avg . Vert,

length change. %

!

t

t

0

( base

)

t

, +0 . 0

0

t

1

j +o . 007

1 ,+0.005

t

Mortar M-l, M-2, M-3

t

t Time, days s/ :

t 1 , 6 70 1 102t

«

t

, Avg. length

, change , %

T

t

t

0 l-o

(base) , .058 1-0.065

t ,-0.065 ,

t t

t Avg . %

, saturation

t

t

t 31.0 1

t 4.7 2.3

t

1 1.7

!

t

1

?

•

Assemblages A- 1 , A-2, A3

t Time, days ,

t (water)

28

, +7 (air)

t 35

t t

t +5 ( oven) t +1+8

1 1+0 .

( air) s 84

+18 ( air )

t

102 , r Avg. length ’ change , % ’ 0

( base

)

!

1 + 0.004

t

t

T

1 + 0.014 ’+0.

! t

r t

v 019 ’

»

t

+0

.

1 018 ’

1

T Avg . % ’ saturation 1

t

100.0

( 1 . 9 %

absorp

.

1 34-0

t )'

’ 0

’

! T

t f

1.9 f

?

1

1 .9 ’

1

T

a/ In air only.

Table 5* Results

Mortar

of Phase

m-4, M-5,

I (continued)

M-6

'Time, days ’ (water) ’ +7 (air) ’ +5 (oven) ’ +62 (air) 4/’

102

t »

i

t

’ 28 ’

1 1 35 ; 40

' Avg . length

' change , $

’ 0

’

| (base)|

-0.114 ’ -0.159

; -0.141;

t ?

* Avg . $

t saturation

t

' 100.0 !

, (11.5^ ,

t absorp . )

t

18.1

1

T 0

t

!

! 7.0 |

t 1

s Autoclave expansion (M-5) = +0.087$

t

Bricks B-10, B-20

’Time, days ' ( air ) a/

t 20 * +5 (water)

25

’+10 (air) T +5 (oven

• 35 ' 40

)

’ +62 ( air ) c/

’

1 102 » 'Avg. length

’ change , $

; \j 0

(base

)

'+0.002

t

t

’ 0.000

1

t

*"

^ 1

+ O O O CVi

1 Avg . %

' saturation

100.0

(5.5$

absorp .

)

T 1.5

t

T

’ 0

t

t

’ 0.0 ’

t »

1 ? Autoclave expansion (B-20) = +0.069$

Bricks B-30, B-lj.0

^Time, days

*

t t

(air) a/

25 ,

+1 (water)

26 ,

+9 (air)

35

J+5 (oven) '+62 (air)hj

, 40 , 102

’Avg. length ’

* change , $

’ 0

’ (base) ’ -0.001 ’

t +0.003 ’ -0.004 ' ”0.001 5t J s

| Avg . $

* saturation

r t

s- !

1 Ni

100.0 ’ (6.1$ f absorp . )

3.8

1

-

— 0 0 0

:

_

_

!

f Auto clave expansion (B-30) = +0.087$

t

t a/ stored

b/ m- 4 , min laboratory

6 only

c/ B-10

d/ B-40

only

only
.•

*
Table 6. Results of Phase II

Group 1

Time , days , 102^/ t

i t +7 (oven'

109

1

t + 7 ( water)

, 116

, +28 (air)

1 144

t +l 4 (air)

, 158

’Avg. horiz.

’length change,^

t

’+o.oo4

’

t s

! t

+ 0.012 ’+ 0.021

!

t

’ + 0.030 ’ +0.029

i Is

i—

i

’Avg. vert,

’length change,

%

r

’+ 0 . 004 ’

T t

t f

+0.039 ’+0.047

1

T

’ +0.058 ’ +0.056

1

cti is saturation

i

t

i

' 4-4 '

t t

t t

t t

0 ’ 100.0

’ ( 7 . 4$

’absorp . )

t

’ 24.6 ’ 15.8

• t

L

ength change,

$

r +0 . 019

1

+0.011 T +0.025 t +0.037

* t '

t +0.037

£=; CD (

1 t T t ! C0 ! CO <

'% saturation

t

»

t 2.0 t

r i

t t

0.0 “ 93-6

!

!

’ 10.3 ’ 7.2

Fh

cri

t Length change,^ T -0 . 066 1 -0.115 ’ -0.070 J - 0.142 I -0.143

-P r—

1

^ 1 o S S

1

t % saturation

j

i

’ 5.2 »

T t

t t

0 0^

pu

•OJ

Fh

O

•O

O

OJw

1

— 1

1

— 1

i-!

Cti

• 14.3 > 14-3

Fh

ctf -p Pd

Length change,^ ;

0 . 142 ; -0.192

1 - 0.108| - 0 . 166

J -0.169

Fh i I

s

t saturation

t 1

t 7.3 » 0.0

T

t 102.9 t 17.6 t 17.6

J is!

n

t Length change,^ t +0 . 002 j 0.000 1+0.004 | +0.014 J +0.015

t

i

i

t

t

t

'i

i

!

»

?

?

J

S

1

» I

1

!

t

? 1

T

t

!

k. I

t

f

V

T

t o o

°H i —

I

F-, I FQ FQ % saturation 0.0 0.0 103.0 0.0 0.0

O

Length change, $ +0.069 +0.057 +0.060 + 0.068 + 0.068

% saturation 2.5 1.7 102.5 2.5 2.5

cf. Phase I
.

.

,* .
Table 6. Results of Phase II (Continued)

Group 2

a/ t 102“ t

* +7 ( water)

109

! ’ Avg. horlz,

! ’length

’

’ change ,%

?

i—i , Avg. vert.

1 ^

f length

’ ^ is t change , %

T ?

? ttlon

j t

’

0 . 002 7 + 0.011

+7( water ) ’ +21 (air) ' +7 ( air )

’ 137 ! 158 ! 165 !

’ + 0.023 ’+ 0.020 »

? t t

, +o . oo 4 i +0.017

! t + 0.026 +0.026 , +0.032 5+O.O3O s

satura- 5.2 . 100.0

> (7.5$

t absorp .

)

31.0 107.8 30.2 25.9

1 h ’ Length

'g c\j

! change , $

© i —-—

m ^ ’ % satura- ^ 1 tlon

?

’+0.019 1 +0.02l|

t ? ^ +0.029 + 0.032 ’ +0.037 ’+0.035 s

t ^ ^ t

! ? 1.9 91.9 16.7 95.7 20.11 15.8

J

j Length

si, change , %

J-0.066J -O.OI4.7 -0.124 •0.096 ’ -0.137 '-0.136 *

5 +1 CVI « j

t o s 1 ^ satura-

, S

'

' f tlon

0 , 100.0

, ( 10 . 6 $

absorp .

)

14.9 113.5 20.9 20.9

cf. Phase I
’
Table 6 . Results of Phase II (Continued)

Group 3

Time, days

? t i

t a/ t +7 ( water ) , ,102-7

f 109

! t t + 7 (oven), + 28 (air) ? +l4(air) f 116 , 144 ? 158 , ’Avg. horiz.

, length change,#

’

0 . 002 * + 0.011 ? ? +0.013 +0.023 +0.023

i t

iH

CCS t »Avg. vert,

i length change,#

, saturation

i+ 0 . 006 t + 0.022 i

t t T +0.059 t + 0 .

0

64 ’ +0.063

, 1.7 f 100.0 , 0 t

t ! (7.5# 1 (base) , j

? absorp. )' *

1.7 1.7

+2g

cd <r\

C0 | cn <!

, # saturation 95.1 0.0 0.4 0.4

in -p cn

P-t ! O S

0.104

i # saturation 0.0 t 100.0 i

t (10.3# T

t absorp . ) t

0 ! (base) j

?

9.1 9.1

Ph

ctf -p

Ph vO O t s s

? Length change,# 7 -O. 141 ? -0.102 0.189 • 0.152 •0.153

? ... .

?

? # saturation 6.6 85 . 5 0.0 10.5 14-5

1 P\ >5^

,

I H d) 1 fQ CO

'

1 o

} »H CD -P P Ph p

? m

Length change,# ? +0 . 083* +0 . 088 +0.070 \ +0.080 J

? # saturation 0.0 130.0 0.0 0.0

+ 0.080

0.0

j Length change,# t -0.001, +0.002 • 0.005 j +0.004 » +0.004

o o

»h —

h

P-t [ PQ PQ # saturation 0.0 124.0 0.0 0.0 0.0

Length change,# ’+0.016’ +0.022 ’ +0.017 ’ +0.029 ’ +0.029

’Length change,# ’-0.062’ -0.034 ’ -0.122 ’ -0.101

t T ? { t

a, cf . Phase I
.

.
Pig. 1. Brick-, mortar-, and assemblage-type volume change specimens

shown with extensometer used to measure the assemblages.

Typical wall volume -change specimen being measured for vertical

length change with 20-inch Wiittemore strain gage.

' t

’

i* :m

L

r
/
LENGTH

CHANGE,

%

TIME DAYS

note: walls not weighed

DURING PHASE X

= IN AIR

FIG. 3 LENGTH CHANGES OF WALLS W-l, W-2, W-3 (PHASE I)

%

OF

SATURATION

REL.

HUMIDITY,

%

TIME DAYS

IOO

80

60

40

20

0

- 0.02 -

0

s

bJo

z

<

X

o

X

I-o

z

UJ

AVERAGE MOISTURE CONTENT

10 20 30 40 50 60 70 80 90 100

10 20 30 40 50 60 70 80 90 100

- 0.10

0.12

= IN AIR

FIG. 4 LENGTH CHANGES a MOISTURE CONTENTS OF MORTAR

SPECIMENS M-l, M-2, M-3 (PHASE I)

%

OF

SATURATION

REL

.

HUMIDITY,

%

TIME DAYS

WATER AIR OVE AIR

IN AIR

IN OVEN — IN WATER

FIG. 5 LENGTH CHANGES 8 MOISTURE CONTENTS OF 3 -COURSE

ASSEMBLAGES A-l, A-2, A-3 (PHASE I)

LENGTH

CHANGE,

%

TIME - DAYS

0 !0 20 30 40 50 60 70 80 90 100

FIG. 6 LENGTH CHANGES 8 MOISTURE CONTENTS OF MORTAR

SPECIMENS M-4, M-5, M -6 (PHASE I)

100

TIME DAYS

FIG. 7 LENGTH CHANGES 8 MOISTURE CONTENTS OF BRICK

SPECIMENS B - 10, B-20, B -30, B-40 (PHASE I)

LENGTH

CHANGE,

%

TIME DAYS

FIG. 8 LENGTH CHANGES OF SPECIMENS TREATED

AS GROUP I (PHASE H

)

LENGTH

CHANGE,

%

TIME DAYS >•

A - 2

v; -2 (AVG. VERT.)

W -2 (AVG. HORIZ.)

M-2

FIG. 9 LENGTH CHANGES OF SPECIMENS TREATED

AS GROUP 2 (PHASE H

)

LENGTH

CHANGE,

%

TIME DAYS

FIG. 10 LENGTH CHANGES OF SPECIMENS TREATED

AS GROUP 3 (PHASE H )

U. S. DEPARTMENT OF COMMERCE

Sim luir \\ reks, Secretary

NATIONAL UUKEAU Ol STANDARD*

A. V'. A st in. Director THE NATIONAL BUREAU OF STANDARDS

The scope of activities of the National Bureau of Standards at its headquarters in Washington,

D. C., and its major field laboratories in Boulder, Colorado, is suggested in the following listing of

the divisions and sections engaged in technical work. In general, each section carries out spe- cialized research, development, and engineering in the field indicated by its title. A brief

description of the activities, and of the resultant reports and publications, appears on the

inside front cover of this report.

WASHINGTON, I). C.

Electricity and Electronics. Resistance and Reactance. Electron Tubes. Electrical Instruments. Magnetic Measurements. Dielectrics, Engineering Electronics. Electronic Instrumentation.

Electrochemistry.

Optics and Metrology. Photometry and Colorimetry. Optical Instruments. Photographic

Technology. Ltyigth. Engineering Metrology.

Heat and Power. Temperature Physics. Thermodynamics. Cryogenic Physics, Rheology

and Lubrication. Engine Fuels.

Atomic and Radiation Physics. Spectroscopy. Radiometry. Mass Spectrometry. Solid State Physics. Electron Physics. Atomic Physics. Nuclear Physics. Radioactivity. X-rays. Betatron. Nucleonic Instrumentation. Radiological Equipment. AEC Radiation Instruments,

Chemistry. Organic Coatings. Surface Chemistry. Organic Chemistry. Analytical Chemistry.

Inorganic Chemistry. Electrodeposition. Gas Chemistry. Physical Chemistry, Thermochemistry. Spectrochemistry. Pure Substances.

Mechanics. Sound. Mechanical Instruments. Fluid Mechanics. Engineering Mechanics.

Mass and Scale. Capacity, Density, and Fluid Meters. Combustion Controls.

Organic and Fibrous Materials. Rubber. Textiles. Paper. Leather. Testing and Specifications. Polymer Structure. Organic Plastics. Dental Research.

Metallurgy. Thermal Metallurgy. Chemical Metallurgy. Mechanical Metallurgy. Corrosion.

Metal Physics.

Mineral Products. Engineering Ceramic.-.. Glast,. Refractories. Enameled Metals. Concreting

Materials. Constitution and Microstructure

Building Technologv, Structural Engineering fire Protection. Heating and Air Conditioning. Floor, Roof, and Wall Coverings. Codes and Specifications.

Applied Mathematics. Numerical Analysis- Computation. Statistical Engineering Mathematical Physics.

Data Processing Systems. SEAC Engineering Group. Components and techniques. Digital

Circuitry. Digital Systems. Analogue Systems. Application Engineering.

• Office of Basic Instrumentation * Office ol Weights and Measures

BOULDER, COLORADO

Cryogenic Engineering. Cryogenic Equipment. Cryogenic Processes. Properties ol Materials.

Gas Liquefaction.

Radio Propagation Physics. Upper Atmosphere Research. Ionospheric Research. Regular

Propagation Services. Sun-Earth Relationships.

Radio Propagation Engineering. Data Reduction Instrumentation. Modulation Systems.

Navigation Systems. Radio Noise. Tropospheric Measurements. 1 ropospheric Analysis. Radio

Systems Application Engineering.

Radio Standards. Radio Frequencies. Microwave Frequencies. High E requency E.lectrieul Standards. Radio Broadcast Service. High Frequency Impedance Standards. Calibration

Center. Microwave Physics. Microwave Circuit Standards.