BuiBauof

tJbniy.N.W.BM|.

Reference book not to be

taken from the Library.

AU6 1 3 1948

Properties of Some

Lightweight-Aggregate Concretes

With and Without an

Air-Entraining Admixture

Building Materials and Structures Report BMS112

United States Department of Commerce

National Bureau of Standards
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UNITED STATES DEPARTMENT OF COMMERCE • Charles Sawyer, S^cr^/«/-y NATIONAL BUREAU OF STANDARDS • E. U. Condon , DiV«(or

Properties of Some

Lightweight-Aggregate Concretes

With and Without an

Air-Entraining Admixture

by Perry H. Petersen

Building Materials and Structures Report BMS112

Issued August 16, 1948

For sale by the Superintendent of Documents, U. S. Government Printing Office, Washington 25, D. C. Price 10 cents
Foreword

This report describes an investigation of the physical properties of several

lightweight-aggregate portland cement concretes made with burned shale or ex- panded slag, undertaken in cooperation with the Federal Public Housing Authority to determine the application of such a concrete in the construction of housing.

The technical facts presented provide data from which architects and engineers can determine whether performance requirements are met.

E. U. Condon, Director.
Properties of Some Lightweight-Aggregate Concretes

With and Without an Air-Entraining Admixture

by Perry H. Petersen

ABSTRACT

The physical properties of several lightweight aggregate portland cement concretes made

with burned shale or expanded slag were investigated at the National Bureau of Standards. Three grades of concrete using each aggregate were made. Air-entrainment of greater than

20 percent is reported for the mixtures leanest in cement, an air-entraining admixture being

used to increase the workability of all but the richest concretes. Compressive, transverse, and bond strengths are given as well as resistance to heat transfer, rain penetration, and

water penetration by capillarity. Also included are the coefficients of thermal expansion,

shrinkage, and values for change in length due to wetting and drying.

CONTENTS

Page

Foreword ii I. Introduction 1 II. Materials 2

III. Concrete - 2 IV. Description of specimens and test results 3

1. Compressive strength 3

2. Flexural strength 4

3. Bond strength to reinforcement 4

4. Heat-transfer properties 5

(a) Shielded hot-box tests 5

(b) Guarded hot-plate tests 5

(c) Results of heat-transfer tests 5

5. Thermal-expansion coefficients 5

6. Shrinkage 6

7. Rain penetration 6 V. Summary 6

I. Introduction

The purpose of an investigation conducted at the

National Bureau of Standards was to determine

the physical properties of several lightweightaggregate concretes in anticipation of their use in the monolithic construction of buildings. These

lightweight aggregates of burned shale or expanded

slag incorporate features that tend to improve heat

insulation more than the aggregates used for dense

concrete. However, if the cement content is low

(3 sacks/yd workability is so poor that placement of the concrete is extremely difficult. Instead of flowing into the forms, the mixture is harsh and the mixing water tends to settle, taking- some cement with it. This fault may be overcome by entraining air in the concrete through the use of an admixture, the entrained au- totaling 20 to 25

percent by volume. When the cement content is in- creased to 10 or 11 sacks/yd ^ of concrete, there is no need for entraining air to increase workability.

For tests described in this report, burned shale

and expanded slag were each used as aggregates in

three grades of concrete ranging upward from a

785795°—48 1
strength of 500 lb/in ^. An air-entraining agent was added to the two leanest mixtures for each ag- gregate but was omitted in the concretes which

were richest in cement.

The properties covered in this investigation in- clude compressive, transverse, and bond strengths,

resistance to heat transfer, water penetration by

capillarity and rain penetration. Values were determined also for shrinkage, for the coefficients of

thermal expansion, and for changes in length due

to wetting and drying.

II. Materials

The cement was a portland cement conforming

to the requirements of Federal Specification SS-C191b . Amendment 1. The burned shale was a lightweight cellular ag- gregate made by burning a certain clay and shale

to incipient fusion. The material was obtained

in two sizes, coarse and fine. The sieve analyses,

absorptions (surface dry), bulk specific gravities,

and the weights per cubic foot of dry material are given in table 1. The expanded slag was a lightweight cellular ag- gregate made from molten hot slag as it comes

from the blast furnace by agitating and cooling it rapidly in an atmosphere of steam. This material

also was furnished in two sizes, coarse and fine. The physical properties are given in table 1

.

The air-entraining admixture was a commercial

product made expressly for entraining air in concrete.

Table 1. Data on aggregates

Aggregate

Grade

Burned shale Expanded slag

Coarse Fine Coarse Fine

Sieve analysis; aggregate passing United States Standard Sieve; H in ___ percent 10088

100 % in. . do.... 98 No. 4 do.... 20 100 34 100

8.. do.... 5 97 13 96

16 do.-.. 4 64 11 76 30 do.._- 3 38 10 49

50. do.-.. 3 25 10 30

100 do... 3 17 9 21 200 do... 2 12 7 14 Absorption (siu-face dry) » 48 hr at 70° F

percent - - 15.8 10.9 36.8 19.0 Bulk specific gravity (oven dry) 1.09 1.54 1.09 1.46 Weight, loose, dry. lb/ft 3-- 37 45 40 57

a Absorption and bulls: specific gravity determined by ASTM methods of

test C 127-42 and 0 128-42, respectively.

III. Concrete

The cement and lightweight aggregates of burned shale and expanded slag were proportioned

by trial batches to produce concretes ranging from

a low to a high cement content. Three mixtures of

each were selected to produce a low-, medium-, and

a high-strength concrete. The burned-shale aggregate, in the original

sacks, was completely immersed in water for 48 hr

and then was allowed to drain, while still sacked,

for 24 hr. The moisture content was determined,

the amount of free water being included as mixing

water in the proportioning of the materials. The

expanded-slag aggregate was used in the dry condition as recommended by producers of this

material.

The materials were proportioned by weight and

the concrete was mixed in a standard 6-ft^ rotary

drum-type mixer. The air-entraining agent, when

used, was introduced with the water and the time

of mixing was in all cases about 5 minutes, as trial mixes indicated that this was the minimum interval

needed to secure complete air entrainment.

All specimens were hand puddled. The forms were stripped at one day, and then the specimens were cured with wet burlap to an age of either 7

days or 28 days as required. They were then

stored in the laboratory until tested. Table 2 lists the data obtained on the fresh concrete, the weight and absorption of the dry concrete, and the compressive strengths of 6- by 12-in. cylinders after aging 28 days. The weight of dry

concrete was obtained after drying the specimens

to constant weight in a chamber maintained at 122° F (50° C) and a lov/ered humidity (approximately 20 to 30 percent) obtained with pans of

calcium chloride. The cement-voids ratio shown

in the table is based on the absolute volume of all the ingredients, the voids including entrained air as

well as all water other than that absorbed in the

aggregate. Water absorption was determined on

oven-dried specimens (220° F) by immersing them

in water at 70° F for 24 hr. Water penetration due to capillarity was determined by placing three specimens of each concrete

in a pan containing water }i to }{ in. in depth. The

specimens were 4 by 4 in. in cross section and about

12 in. high. Observations were made at 1 hr and

at 7 days to determine the height the water rose due to capillarity. The observed heights are given

in table 2.

2 Building Materials and Structures Reports
Table 2. Proportions of ingredients; density and absorption of concretes

Aggregate

Burned shale E.xpanded slag

3.0 6.4 9.9 4.4 6.9 11.0

Air-entraining agent, by weight of cement percent- . ZD NT

IN one . 50 , 25 None

Proportions, by loose volume, dry: Portland cement 1.0 1.0 1.0 1.0 1.0 1.0 6.2 3.2 1.4 2.7 1.5 0.8 Coarse aggregate o. U

o nu 1. 5 2. 2 1.

6

1. 2

2.S 4.3 6.4 4.0 6.0 5.6 Oement voids ^ ratio by absolute volume 122 947 A1

1

. 1/1 . 303 . 652

percent-. 20.8 13.9 (°) (24) (18) (o) Weight of concrete: Fresh _ lb/ft.3.. 74.0 83.4 101. 2 72.9 81.3 102.8 Dry lb/tt.3._ 60.3 71.4 88. 2 65.1 72.8 96.2 Water absorption, 24 hr at 70° F by dry weight percent-. 23.1 14.0 10.0 21.4 14.6 10.0

Capillary rise of water: At 1 hr 1.9 1.3 1.0 .9 1.1 .9 8.5 4.7 4.0 6.3 4.6 4.8 Compressive strength a at 28 days: Cured 7 days wet, 21 days in air -lb/in.3.. 530 2,240 6,090 770 1, 660 3, 540

» Voids=entrained air and mixing water,

b Values in parentheses are estimated.

" Negligible.

d See table 3 for additional data.

IV. Description of specimens and test results

1. Compressive strength

The specimens for compressive strength tests included 6- by 12-in. cylinders and some wallettes

8 by 30 by 30 in. The wallettes were used primarily

to obtain values of shrinkage and were then tested

in compression at the termination of those observations.

Values for the secant modulus of elasticity were

obtained on cylinders wet-cured for 28 days by

means of Tuckerman extensometers with a 6-ui. gage length. The moduli were determined at

stresses of 200, 800, and 2,000 Ib/in.^, respectively,

for the three grades of concrete. These values and

the compressive strength values are given in table 3.

Table 3. Compressive and flexural strengths of concrete specimens *

Aggregate

Burned shale Expanded slag

Cement content sacks/yd.s_. 3.0 5.4 9.9 4.4 6.9 11.0

Compi-essive strength: Cylinders, 6- by 12-in. Age 7 days, wet-cured lb/in.2.. 230 1,110 4,250 310 960 2, 560 Age 28 days, wet-cured--. - - lb/in.2.. 480 1.730 5, 720 590 1, 510 3,380 Age 28 days, 7 wet- and 21 air-cured. lb/in.2-. 530 2,240 6, 090 770 1,660 3, 540 Age 2 yr, 7 days wet-cured lb/in.2-

650 2,590 5. 850 860 1, 570 3, 100 Wallettes, 30- by 30- by 8-in. Age 2 yr, 7 days wet-cured lb/in.2-- 1,030 2,970 5, 380 810 1,590 3,150 Secant modulus of elasticity, 6- by 12-in. cylinder: Age 28 days wet-cured: At 200 lb/in.2 lb/in.2-

720, 000 615, 000 At 800 lb/in.2 lb/in.2-

1, 240, 000 1, 050, 000 At 2000 lb/in.2 -lb/in.2-. 2, 170, 000 2, 000, 000 Modulus of rupture in flexure of 4- by 4-in. bars: Age 28 days, 7 wet- and 21 air-cured - --- lb/in.2. _ 153 398 690 183 333 656

» All values are the average for 3 specimens, except in the case of wallettes, of which there was only one specimen each.

Properties oj Lightweight-Aggregate Concretes 3
2. Flexural Strength

Flexural strength tests were made on bars 4 by 4

in. in cross section and 30 in. long, at an age of 28

days. The bars were supported as a simple beam

on a span of 24 in., and were loaded at the center with the screeded side of the concrete in compression. The computed values for themodulus of rupture are included in table 3.

3. Bond Strength to Reinforcement

Reinforced concrete beams were made of the two

strongest grades of each concrete with two makes

of bar represented. Bond strengths after 28 days

of wet curing were determined for lengths of em- bedment of 10, 20, and 30 in. by making and test- ing beams of different lengths. A sketch of the

beams is shown in figure 1.

12"

Load-, i 4 S^/rrupa 2" c.CI ! I M I I I I I >

! I I '

-Bond destroyed 2'a/' each end

of beam

5-ir r. sfra/n gage

A = length of embedmen-t

Figure 1. Sketch of beams for bond strength tests.

The two bars represented are shown in figure 2 and have nominal diameters of 1 in. The deformations on bar A are of the double helix pattern,

reversing direction on the two faces of the bar.

The deformations on bar B are of the diamondpatterned type. The tensile properties determined

for each bar are given in table 4.

Table 4. Tensile properties of reinforcing bars

Bar A Bar B

Cross-sectional area. .

.

in 2.. 0. 796 0. 788 Yield point- ..... . . Ih/in 2.. 60. 400 52. 000 Tensile strength... lb/in 2.. 94, 200 92. 300 Elongation in 8 in . . . percent.. 18.8 23. 1

Most of the specimens exhibited bond failures,

but in some the reinforcing bars yielded in tension.

Where the latter occurred, bond stress values were

based on the load at which yielding of the reinforcement occurred. Whittemore strain-gage readings on a 5-in. gage length were made on the steel at the center of the beam through holes in the concrete. Slip at the ends of the bar was measured

by using 0.0001-in. dial indicators fastened to two

lugs embedded in the concrete, the dial stem being

in contact with the end of the bar.

BAR "A" . BAR B FiouRE 2. Types of bars for bond strength tests. The computed bond stresses at an initial slip of

0.001 in., and the bond strength are given in

table 5. Table 5. Bond strengths between concrete and

reinforcement bars

Cement content sacks/yd.'. Compressive strength, 28 da wet lb/in.2. Bond stress at 0.001 in. slip: Bar A:

10-in. embedment Ib/in.^. 20-in. embedment lb/in. 30-in. embedment lb/in. 2. Bar B:

10-in. embedment lb/in.*. 20-in. embedment lb/in. 2. 30-in. embedment lb/in. 2. Bond strength: Bar A:

10-in. embedment lb/in. 20-in. embedment lb/in. 2. 30-in. embedment . lb/in.2. Bar B:

10-in. embedment lb/in. 2. 20-in. embedment.. lb/in. 2.. 30-in. embedment lb/in. i^.

Aggregate

Burned

shale Expandedslag

5.4 9.9 6.9 11.0

1,730 6, 720 1,510 3, 380

320 425

420

647

600

» 520

283 320

307

440

500

" 520

182

175

1.57

528 425

" 450

212

165

180

430

340

» 450

341 506

" 620

820

» 790

« 520

318

374 328

440

610

" 520

310 385

267

019

« 680

« 450

231

221 252

530

544 1450

' Bond stress at tensile yielding of bars.

Building Materials and Structures Reports
4. Heat- transfer properties

Two types of specimens of each concrete were made for the heat-transfer tests, one for use in the

I shielded hot box and one to be tested by means of

the guarded hot plate.

(a) Shielded hot-box tests The walls for the shielded hot-box tests were 100

in. high, 8 in. thick, and 56 in. wide, and were

tested at an age of 18 to 24 months, having been in

storage in the laboratory for that length of time.

They had been wet-cured for the first 7 days and

exposed to the air for the remainder of the period.

The heat-transfer section of this bureau con- ducted the tests in a shielded hot-box apparatus designed for the purpose. During the test, heat

flowed from the metering and shield boxes (which were heated electrically) through the wall to the

cold box, which was cooled by a refrigerating machine. The electric energy supplied to the metering

box and measured by a watt-hour meter was closely

equivalent to the heat energy transferred through

the portion of the wall covered by the metering box.

The temperatures in the metering and shielded

boxes were the same and were kept at 70° F; the

temperature in the cold box was kept at 0° F,

making the mean temperature approximately 35°

F. Air temperatures and surface temperatures on

both sides of the wall were measured by means of

thermocouples.

(b) Guarded hot-plate tests The specimens for the guarded hot-plate tests were 8 by 8 in. in plan and about 1 in. in thickness.

They were cut from an 8-in. wall sample with one

8-in. dimension parallel to the thickness of the wall

the other parallel to the height of the wall, and the

1-in. dimension parallel to the width of the wall. The apparatus consisted of an electrically heated

flat hot plate, 8 in. square, flanked on each side by

a cold plate that was cooled by a flow of water at constant temperature. Two like specimens of

each concrete were used, one being placed on each

side of the hot plate and between it and the adja- cent cold plate. The heat flowing through a

central metering area 4 in. square was measured

and the heat conductivity of the material com-,

puted. The average mean temperature of the

hot-plate specimens was approximately 68° F. Immediately after testing, these specimens were

dried for 24 hr at 230° F in order to ascertain the

moisture content of the concrete at the time of test.

(c) Results of heat-transfer tests The results of the observations on heat-transfer

tests are given in table 6. The heat transmission is expressed in two ways: by the over-all heat

transmittance, U, of the 8-in. wall, and by the thermal conductivity, k. Both heat-transfer coeffi- cients were computed for each type of test to provide a comparison of values obtained by the two

methods. It is believed that the moisture content

oi the large walls was considerably greater than

that of the small specimens used in the hot-plate

tests, and that the higher values obtained in the

hot-box tests are due to this greater moisture content. The magnitude of this effect is indicated in

table 6 by the two hot-plate tests made at different

moisture contents on the burned-shale specimen

leanest in cement.

Table 6. Heat-transfer coefficients

Aggregate

Burned shale Expanded slag

Cement content sacks/yd. 3.0 5.4 9.9 4.4 6.9 11.0

Shielded hot-box data: Thickness of walls _ in... 8.05 8. 06 8.02 8.00 8. 00 8.00 Corrected thermal transmittance,* V 0.26 0.32 0.41 0.24 0. 30 0. 38 Thermal conductivity,'' k 2.60 3.44 4. 88 2.41 3. 13 4. 34 Guarded hot-plate data: Thickness of specimen _ .in... 1.02 0.99 1.06 1.06 1.03 1.06 Dry density. -- - ..lb/ft.3.. 61.0 68.8 84.0 61.5 71.4 94.4 Moisture content as tested. perc<!nt-. 1.7 7.3 3.1 5.0 2.5 3.5 4.5 Thermal conductivity,'' k 1. 87 2. 31 2.29 3. 01 1.77 2.27 3. 42 Computed value of thermal transmittance for 8-in. v^all," U 0. 20 0. 24 0.24 0.29 0. 19 0.23 0. 32

" (7=number of Btu per hour transmitted throueh each square foot of specimen for each degree Fahrenheit difference in- temperature between the air on the two sides for a condition of still air on the warm side and a 15-mph wind on the cold side,

b A=number of Btu per hour transmitted through each square foot of specimen for each degree Fahrenheit temperature difference in the material per inch

f thickness.

5. Thermal-expansion coefficients

Six specimens, IK in. square and 9 in. long, were

cut from specimens of each concrete. Data were

obtained with a 6-in. Tuckerman optical strain

gage operating on specimens placed in a temperature-controlled box equipped with observation

portholes. Readings were made at two extremes

of temperature, lp4° F (40° C) and 14° F (-10° C), a full cycle requiring 24 hr. Measurements were

Properties of Lightweight-Aggregate Concretes 5
Table 7. Length changes due to temperature, wetting and drying, and drying shrinkage

Aggregate

Burned shale Expanded slag

3.0 5.4 9.9 4.4 6.9 11,0

10~^/° F 3.6 4.1 4.5 5.1 5.5 6.2 Shrinkage of 8-m. thick wallettes in laboratory air: At 2yr 10-« in./in... -440 -660

-180

-410

>+160 "+160 -800

-960

-710

-1, 060 -360 -710

Changes in length b during wetting and drying at 70° F 10-6 in./in... -270 -500 -600 -400 -630 -970

» The plus sign denotes an expansion of 0.000160 in./in.

*> Values signify shrinkage on drying cycle and are equal and opposite to expansion on wetting. made for a number of cycles until the readings indicated no progressive changes in length. The

temperature of the air surrounding the specimens was determined with calibrated copper-wire re- sistance thermometers and was controlled with a bimetal thermoregulator to ±0.2 deg F. The coefficients of thermal expansion were

determined for six like specimens, and the average

for each concrete is reported in table 7.

6. Shrinkage

Shrinkage was measured on wallettes 8 in. thick,

30 in. high, and 30 in. wide. Changes in the verti- cal direction beginning at an age of 1 week were

obtained with a 20-in. Whittemore strain gage.

The specimens were stored in laboratory air, and

measurements were made over a period of 2 years. Values for change in length due to wetting and

drying were also obtained. These measurements

were made using a vertical comparator on speci- mens 1% in. square and 7 in. long; the specimens were cut from larger pieces of the concrete. When

18 to 24 months old, they were fully wetted for a week in water at 70° F, then dried to constant

length at 70° F and 40-percent relative humidity.

They were then immersed for 48 hr. and again

dried to constant length, several of these cycles

being made. Measurements of changes in length were noted from the start, and it was found that

there was but a slight change from cycle to cycle.

Values of shrinkage in laboratory air and those

of change in length during wetting and drying are shown in table 7.

7. Rain Penetration

The sLx specimens used for the water permeability tests, one of each mix, were about 51 in. high,

41 in. wide, and 8 in. thick. They were built on

supporting channels with a 2-in. mortar base containing a copper flashing projecting at the back.

The surfaces were not finished in any way ; the walls were tested at an age of 3 months in their original

condition.

The water-permeability test is described in

Building Materials and Structures Report BMS82,

Water permeability of walls built of masonry

units.^ The specimens were supported on metal

skids, and when clamped in position, the exposed

face formed one side of a pressure chamber. An

air pressure of 10 Ib/ft^ above atmospheric pressure was maintained in the chamber, and water from a

perforated tube was sprayed near the top edge of

the exposed face at the rate of 40 gal/hr.

The arbitrary method of rating the performance

as given in BMS82 was employed. All the walls were judged to be excellent because no visible

water appeared above the flashings in 1 day, and in 5 days there was no leakage and less than 25 per- cent of damp wall area.

1 Obtainahle from the Superintendent of Documents, Government Printing

Oflice, Washington 25, D. C, for 20 cents.

V. Summary

Specimens of lightweight-aggregate concretes made with burned shale or an expanded slag as the sole aggregates were tested for various physical

properties.

Tliree grades of each concrete were made: a lean, an intermediate, and a rich concrete. The cement

contents were 3.0, 5.4, and 9.9 sacks/yd^, respectively, for the concretes with burned shale as the

aggregate and 4.4, 6.9, 11.0 for the concretes made

with expanded shig. An air-entraining agent was

used with the portland cement in all but the richest

mixtures of each type of concrete. The leanest

mixtures with each aggregate had compressive

strengths of 500 to 800 Ib/in.^ and dry weights of 60

to 65 Ib/ft^ Walls of this low-cement, high-void

concrete possess heat-transfer properties suitable

for insulation in some tvpes of buildings. Hotplate test values of 1.8 and 1.9 Btu in. hx'^ ft^^ "F'^

for thermal conductivity compare very favorably

with values of 10 to 16 for ordinary dense concrete. Heat transfer, compressive strength, and density all increased with increase in cement content. 6 Building Materials and Structures Reports
but thermal conductivity increased only to 3.0 and 3.4 for the dense mixtures, which is still a rel- atively low value for monolithic concrete. Tests show that concrete with a compressive

strength of 6,000 lb/in. ^ can be made by using

burned-shale aggregate ; the expanded-slag mixture

with a cement content of 11 sacks/yd^ had a compressive strength of 3,500 Ib/in^. The ratio of

compressive to transverse strengths was about the same as for ordinary sand and gravel concrete, al- though more cement was required with the lightweight aggregates to obtain equivalent strengths.

The modulus of elasticity was 2,170,000 Ib/in.^ for a burnt shale aggregare concrete of 5,000-lb/in.^

compressive strength.

Bond strength between the concrete and the

steel reinforcement was about the same as for ordinary dense aggregate concrete of the same compressive strength.

Coefficients of thermal expansion for the lightweight-aggregate concretes made with burned

shale ranged from 3.6 to 4.5X 10~® per ° F, and from

5.1 to 6.2X10"^ for those made with expanded slag.

All of the mixtures showed normal shrinkage ranging from 0.02 to 0.10 percent, except the burnedshale concrete richest in cement. This exhibited an expansion of almost 0.02 percent when stored in laboratory air for a period of one year. Length

changes diu'ing wetting and drying ranged from

270 to 600 X lO"** for the burned shale aggregate concretes and from 400 to 970X10~'*for the expanded

slag aggregate concretes ; they were smallest for the

lean concretes and largest for the rich concretes. Resistance of walls to rain penetration was shown to be excellent.

The heat-transfer properties were determined by

H. E. Robinson of the Bureau's Heat Transfer Section; the water permeability properties by C. C.

Fishburn, qf the Masonry Construction Section.

Washington, November 28, 1947.

Properties of Lightweight-Aggregate Concretes

U. S. GOVERNMENT PRINTING OFFICE: 194] 7
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BUILDING MATERIALS AND STRUCTURES REPORTS

[Continued from cover page ii] BMS32 Structural Properties of Two Brick-Concrete-Block Wall Constructions and a Concrete-Block WaU Construction Sponsored by the National Concrete Masonry

Association 15^ BMS33 Plastic Calking Materials 15^ 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 WaUs, Partitions, and

Floors, Sponsored by Palisade Homes * BMS38 Structural Properties of Two "Dunstone" Wall Constructions Sponsored by the W. E. Dunn Manufacturing Co lOjS BMS39 Structural Properties of a Wall Construction of "Pfeifer Units" Sponsored by the Wisconsin Units Co 100 BMS40 Structural Properties of a Wall Construction of "Knap Concrete Wall Units" Sponsored by Knap America, Inc 15jS BMS41 Effect of Heating and Cooling on the Permeability of Masonry Walls * BMS42 Structural Properties of Wood-Frame Wall and Partition Constructions with "Celotex"

Insulating Boards Sponsored by The Celotex Corporation 15(4 BMS43 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 2 15(6 BMS44 Surface Treatment of Steel Prior to Painting 10^ BMS45 Air Infiltration Through Windows 150 BMS46 Structural Properties of "Scott-Bilt" Prefabricated Sheet-Steel Constructions for Walls, Floors, and Roofs Sponsored by The Globe-Wernicke Co 100 BMS47 Structural Properties of Prefabricated Wood-Frame Constructions for Walls, Partitions, and Floors Sponsored by American Houses, Inc 200 BMS48 ' Structural Properties of "Precision-Built" Frame WaU and Partition Constructions

Sponsored by the Homasote Co 150 BMS49 Metallic Roofing for Low-Cost House Construction 200 BMS50 Stability of Fiber Building Boards as Determined by Accelerated Aging 100 BMS51 Structural Properties of "Tilecrete Type A" Floor Construction Sponsored by the

Tilecrete Co 100 BMS52 Effect of Ceiling Insulation Upon Summer Comfort , 100 BMS53 Structural Properties of a Masonry Wall Construction of "Munlock Dry Wall Brick"

Sponsored by the Munlock Engineering Co 100 BMS54 Effect of Soot on the Rating of an Oil-Fired Heating Boiler 100 BMS55 Effects of Wetting and Drying on the Permeability of Masonry WaUs 100 BMS56 A Survey of Humidities in Residences 100 BMS57 Roofing in the United States—Results of a Questionnaire * BMS58 Strength of Soft-Soldered Joints in Copper Tubing 100 BMS59 Properties of Adhesives for Floor Coverings 100 BMS60 Strength, Absorption, and Resistance to Laboratory Freezing and Thawing of Building Bricks Produced in the United States 150 BMS61 Structural Properties of Two Nonreinforced Monolithic Concrete Wall Constructions. 100 BMS62 Structural Properties of a Precast Joist Concrete Floor Construction Sponsored by

the Portland Cement Association 100 BMS63 Moisture Condensation in Building Walls 150 BMS64 Solar Heating of Various Surfaces 100 BMS65 Methods of Estimating Loads in Plumbing Systems 150 BMS66 Plumbing Manual * BMS67 Structural Properties of "Mu-Steel" Prefabricated Sheet-Steel Constructions for Walls, Partitions, Floor, and Roofs, Sponsored by Herman A. Mugler 150 BMS68 Performance Test for Floor Coverings for Use in Low-Cost Housing: Part 3 200 BMS69 Stability of Fiber Sheathing Boards as Determined by Accelerated Aging 100 BMS70 Asphalt-Prepared Roll Roofings and Shingles 200 BMS71 Fire Tests of Wood- and Metal-Framed Partitions 200 BMS72 Structural Properties of "Precision-Built, Jr." Prefabricated Wood-Frame Wall

Construction Sponsored by the Homasote Co 100 BMS73 Indentation Characteristics of Floor Coverings 10^ 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 150 BMS75 Survey of Roofing Materials in the North Central States 150 BMS76 Effect of Outdoor Exposure on the Water Permeability of Masonry WaUs 150 BMS77 Properties and Performance bf Fiber Tile Boards 100 BMS78 Structural, Heat-Transfer, and Water-PermeabiUty Properties of Five Earth-Wall

Constructions 250

BMS79 Water-Distributing Systems for BuUdings 200 BMS80 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 4 150 BMS81 Field Inspectors' Check List for Building Constructions (cloth cover, 5x7}^ inches).. 200

•Out of print. (List continued on cover page iv]
BUILDING MATERIALS AND STRUCTURES REPORTS

[Continued from cover page m] , BMS82 Water Permeability of Walls Built of Masonry Units 25(S BMS83 Strength of Sleeve Joints in Copper Tubing Made With Various Lead-Base Solders 100 BMS84 Survey of Roofing Materials in the South Central States 15^ BMS85 Dimensional Changes of Floor Coverings With Changes in Relative Humidity and

Temperature 10j5 BMS86 Structural, Heat-Transfer, and Water-Permeability Properties of "Speedbrik" Wall

Construction Sponsored by the General Shale Products Corporation 15j5 BMS87 A Method for Developing Specifications for Building Construction—Report of Subcommittee on Specifications of the Central Housing Committee on Research,

Design, and Construction 150 BMS88 Recommended Building Code Requirements for New Dwelling Construction With

Special Reference to War Housing * 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 150 BMS92 Fire-Resistance Classifications of Building Constructions 300 BMS93 Accumulation of Moisture in Walls of Frame Construction During Winter Exposure. _ 100 BMS94 Water Permeability and Weathering Resistance of Stucco-Faced, Gunite-Faced, and

"Knap Concrete-Unit" Walls 100 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 Fii)er Insulating Board 100 BMS98 Physical Properties of Terrazzo Aggregates 150 BMS99 Structural and Heat-Transfer Properties of "Multiple Box-Girder Plywood Panels"

for Walls, Floors, and Roofs 150 BMSlOO Relative SHpperiness of Floor and Deck Surfaces 100 BMSlOl Strength and Resistance to Corrosion of Ties for Cavity Walls 100 BMS102 Painting Steel 100 BMS103 Measurements of Heat Losses From Slab Floors 100 BMS104 Structural Properties of Prefabricated Plywood Lightweight Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by the Douglas Fir Plywood Association . 250 BMS105 Paint Manual $1. 00

BMS106 Laboratory Observations of Condensation in Wall Specimens * BMS107 Building Code Requirements for New Dwelling Construction 200 BMS108 Temperature Distribution in a Test Bungalow With Various Heating Devices 100 BMSlOO Strength of Houses: Application of Engineering Principles to Structural Design $1. 50

BMSllO Paints for Exterior Masonry Walls 150 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 100

•Out of print.

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