U. S. DEPARTMENT OF COMMERCE
The program of research on building materials and structures, carried on by the

National Bureau of Standards, was undertaken with the assistance of the Central

Housing Committee, an informal organization of governmental agencies concerned

with housing construction and finance, which is cooperating in the investigations through

a subcommittee of principal technical assistants.

CENTKAL HOUSING COMMITTEE

SUBCOMMITTEE ON TECHNICAL RESEARCH

Walter Junge, Chairman.

Federal Housing Administration.

Sterling R.

Albert G. Bear,

Veterans' Administration.

Pierre Blouke,

Federal Home Loan Bank Board

(Federal Loan Agency).

Carroll W. Chamberlain,

Public Buildings Administration (Federal Works Agency).

Joseph M. DallaValle,

Public Health Service (Federal Security

Agency).

John Donovan,

Farm Security Administration (Agriculture).

A. C. Shire, Vice Chairman.

United States Housing Authority.

March, Secretary.

George E. Knox,

Yards and Docks (Navy).

Vincent B. Phelan,

National Bureau of Standards (Commerce).

Edward A. Poynton,

Office of Indian Affairs (Interior).

George W. Trayer,

Forest Service (Agriculture).

Elsmere J. Walters,

Construction Division (War).

CHAIRMEN OF SECTIONS

Specifications Maintenance Mechanical Equipment

Carroll W. Chamberlain Charles Peters Robert K. Thulman

NATIONAL BUREAU OF STANDARDS

STAFF COMMITTEE ON ADMINISTRATION AND COORDINATION

Hugh L. Dryden, Chairman.

Mechanics and Sound

Phaon H. Bates, Gustav E. F. Lundell,

Clay and Silicate Products. Chemistry.

Hobart C. Dickinson, Addams S. McAllister,

Heat and Power. Codes and Specifications.

Warren E. Emley, Henry S. Rawdon,

Organic and Fibrous Materials. Metallurgy.

The Forest Products Laboratory of the United States Department of Agriculture

is cooperating with both committees on investigations of wood constructions.

[For list of BMS publications and how to purchase, see cover page III]
UNITED STATES DEPARTMENT OF COMMERCE • Harry E. [ lopkins, Secretary

NATIONAL BUREAU OF STANDARDS • Lyman J. Hrigf,'.s, Director BUILDING MATERIALS

and STRUCTURES

REPORT BMS51

Structural Properties of "Tilecrete Type A"

Floor Construction Sponsored by the Tilecrete Co.

by HERBERT L. WHITTEMORE, AMBROSE H. STANG,

and DOUGLAS e. parsons

ISSUED JUNE 4, 1940

The National Bureau of Standards is a fact-finding organization;

it does not "approve" any particular material or method of construction. The technical findings in this series of reports are to be construed accordingly.

UNITED STATES GOVERNMENT PRINTING OFFICE • WASHINGTON 194©

FOR SALE BY THE SUPERINTENDENT OF DOCUMENTS, WASHINGTON, D. C. • PRICE lO CENTS
Foreword

This report is one of a series issued by the National Bureau of Standards on the

structural properties of constructions intended for low-cost houses and apartments.

These constructions were sponsored by organizations within the building industry

advocating and promoting their use. The sponsor built and submitted the specimens

described in this report for participation in the program outlined in BMS2, Methods of

Determining the Structural Properties of Low-Cost House Constructions. The sponsor,

therefore, is responsible for the design of the construction and the description of materials

and methods of fabrication. The Bureau is responsible for the method of testing and

for the test results. This report covers only the load-deformation relations and strength of the structural element when subjected to transverse, impact, and concentrated loads by standardized methods simulating the loads to which the element would be subjected in actual

service. Later, it may be feasible to determine the heat transmission at ordinary

temperatures and the fire resistance of these same constructions.

The National Bureau of Standards does not "approve" a construction, nor does it express an opinion as to the merits of a construction, for the reasons given in reports

BMSl and BMS2. The technical facts presented m this series provide the basic data

from which architects and engineers can determine whether a construction meets desired

performance requirements.

Lyman J. Briggs, Director.

[II]
Structural Properties of " Tilecrete Type A" Floor Construction

Sponsored by the Tilecrete Co.

by HERBERT L. WHITTEMORE, AMBROSE H. STANG, and DOIJCJLAS E. PARSONS

CONTENTS

Page Page Foreword ii IV. Floor CT—Contitmed.

I. Introduction 1 1. Sponsor's statement—Continued.

II. Sponsor and product 2 (c) Comments 6

III. Specimens and tests 2 2. Transverse load 7 IV. Floor CT 3 3. Impact load 9

1. Sponsor's statement 3 4. Concentrated load 10

(a) Materials 3

(b) Description of specimens 5

ABSTRACT

For the program on the determination of the struc- tural properties of low-cost house, constructions, the

Tilecrete Co. submitted six specimens representing its "Tilecrete Type A" floor construction. The specimens were subjected to transverse, impact,

and concentrated loads. For each of the loads three

like specimens were tested. The deformation under

load and the set after the load was removed were measured for uniform increments of load. The

strength under transverse load was also determined.

The results are presented in graphs and in a table.

I. INTRODUCTION

To provide technical facts on the perfonn- ance of constructions which might be used in

low-cost houses, to discover promising new

constructions, and ultimately to determine the

properties necessary for acceptable performance

in actual service, the National Bureau of Standards has invited the cooperation of the

building industry in a progTam of research on

building materials and structures suitable for low-cost houses and apartments. The objectives of this program are described in report

BMSl, Research on Building Materials and

Structtu-es for Use in Low-Cost Housing, and

that part of the program relating to structiual

properties in report BMS2, Methods of Determining the Structural Properties of Low-Cost

House Constructions.

Masonry constructions and wood constructions of types which have been extensively used

in this country for houses were included in the

program because their beliavior imder widely

different service conditions is known to builders

and the public. The reports on these constructions are BMS5, Structural Properties of Six Masonry Wall Constructions, and BMS25,

Structural Properties of Conventional WoodFrame Constructions for Walls, Partitions,

Floors, and Roofs. The masonry specimens were built by the Masonry Construction Section of this Bureau, and the wood-frame speci- mens were built and tested by the Forest Products Laboratory at Madison, Wis.

The present report describes the structural

properties of a floor construction sponsored by

one of the manufacturers in the building in- dustry. Transverse, mipact, and concentrated

loads were applied to the specimens, siniidatmg

the loads to which the floors of a house would

be subjected in actual service. Transverse

loads are applied to floors by fm-niture and

occupants; impact loads by objects falling on

the floor or by persons jumping on the floor; and concentrated loads by furnitme, for ex- ample, the legs of a piano.

The deflection and set mider each increment

of load were measured because the suitability

of a floor construction depends not only on its resistance to deformation when loads are applied, but also on whether it retiu-ns to its original size and shape when the loads are removed.

[1]
II. SPONSOR AND PRODUCT

The specimens were submitted by Tilecrete

Co., Washington, D. C, and represented its "TUecrete Type A" floor construction, consisting of expanded steel joists, asbestos-cement

fillers, concrete fill, and a white-oak finish

floor. Structural Properties of a "Tilecrete" Floor

Construction Sponsored by Tilecrete Floors,

Inc., BMS16, reports the results of tests on

"Tilecrete Type T" floor construction submitted

by the same organization. Type T construction consisted of expanded steel joists, tile

fillers, concrete fill, and a finish floor.

III. SPECIMENS AND TESTS

The floor construction was assigned the

symbol CT and the individual specimens were

assigned the designations given in table 1.

Table 1.

Specimen designations, floor CT

Specimen designation Load Load applied

T1,T2,TS.... Transverse Upper face.

11, 12,13 Impact Do.

PI, P^, PS^ - --- Concentrated Do.

» The concentrated and impact loads were applied to the same speci- mens. The impact loads were applied first.

Except as mentioned below, the specimens were tested in accordance with the procedure

outlined in BMS2, which report also gives the

requirements for the specimens and describes

the presentation of the results of the tests, particularly the load-deformation graphs.

To prevent misleading results of the impact

test due to local effects on the loaded face of this

type of specimen, the deflections and sets were measured with two deflectometers and two set gages, not one, as described in BMS2. The

deflectometers were placed in contact with the

unloaded face of the specimen at midspan, one

at each joist, and the set gages rested on the

loaded face, one over each joist.

The indentation under concentrated load and

the set after the load was removed were measured, not the set only, as described in BMS2.

The apparatus is shown in figure 1

The load was applied to the thick steel disk,

A, to which the crossbar, B, was ligidly atFiGURE 1.

Apparatus for concentrated-load test.

A, disk; B, crossbar; C, spring dynamometer; D, stand; E, dial micrometer.

tached. The load was measured by means of the dynamometer, C. The dynamometer was

of either the spring type or the ring type. Two

stands, D, rested on the face of the specimen,

each supporting a dial micrometer, E, the spindle of which was in contact with the crossbar

8 in. from the disk. The micrometers were

graduated to 0.001 in., and readings were re- corded to the nearest division. The initial reading (average of the micrometer readings) was observed under the initial load, wliich included the weight of the disk and dynamometer.

A load was applied to the disk and the average

of the micrometer readings minus the initial reading was taken as the depth of the indentation imder load. The set after the load was removed was determined similarly.

The specimens were tested on October 3 and

4, 1939, on the 28th day after the pouring of the concrete fill. The sponsor's representative

witnessed the tests.

[2]
Figure 2.

Expanded steel joist, floor CT.

IV. FLOOR CT

1. Sponsor's Statement

The information for this statement was obtained from the sponsor and from inspection of the specunens. The Masonry Construction

Section of the National Bm'eau of Standards

assisted by determining the physical properties

of the concrete and of the asbestos-cement

fillers, the Engineering Mechanics Section by

determining the moisture content of the wood

flooring, and the Forest Products Laboratory by

identifying the species of wood in the flooring.

(a) Materials

Expanded steel joists.—Open-hearth, hotrolled, one-piece membei's, 12 ft 7% in. long,

6 in. deep; weighing 4.1 lb/ft; manufactured

from special I-beams by a continuous process

of hot-rolling, slitting, and expanding. They

were straightened by cold-rolling. The panellength of the web was 1 ft 4%^ in. A joist is

shown in figm-e 2. The end struts, fastened by

arc welds, reinforced the joists at the supports.

The chemical composition of the steel is given in table 2 and the mechanical properties in table 3. Table 2.

Chemical composition of the steel in the joists, floor CT

Element Content

Percent Carbon.. 0.23 Manganese .45 Phosphorus. . .on

Sulfur .030

Table 3.

Mechanical properties of the steel in the

joists, floor CT

Yield

point

Tensile strength Elongation

in 8 in.

Ibjin.^ 42,000

lb/in.'

04, 300 Percent

23.7

"Bethlehem Open-Web Expanded St(H4 Joist,

Type 62", Bethlehem Steel Corporation.

[3]
i

Concrete.—Transit-mixed, containing 1 part

of Portland cement, 2.5 parts of sand, and 4.3

parts of gravel (maximum size, 1 in), by dry

weight, with 6 to 8 gal of water per sack of

cement (94 lb) . The concrete was dehvered in three batches.

For each batch the slump was determined in accordance with ASTM Standard D 138-32T,

and six 6- by 12-in. cylinders were made.

Three cylinders were stored in air near the

floor specimens, and the other tlu-ee were stored

at 70° F and a relative humidity of 95 to 100

percent. The compressive strength of each

cylinder was determined on the day the cor- responding floor specimen was tested, age 28

days. The physical properties of the concrete

are given in table 4. Table 4.

Physical properties of the concrete, floor CT

Batch Slump

Compressive strength

Cylinders cured with

floor specimens

Cylinders

cured at 70° F and 95- to 100-percent

relative humidity

in.7

Iblin.'2,010

2,460

2, 360

Ib/in.^

2 2,920

2. 660 3 ---

The sand and gravel were obtained from pits near Bowie, Md.; portland cement, "Alpha"

brand, from the Alpha Portland Cement Co.;

concrete, from the Transit-Mixed Concrete

Co., Wasliington, D. C.

Asbestos-cement fillers. —Full-sized asbestoscement fillers, as shown in figure 3, 1 ft 11 '5^6 in.

long, 1 ft 11^^ in. wide (range 1 ft 11% in. to 1 ft 11% in), and ji in. thick. The depth of the fillers was 3^{6 in. The half-sized fillers were the same

as full-sized fillers cut along the longitudinal

center line. Table 5.

Physical properties of the asbestos-cement

fillers, floor Cf »

Water content, by

weight Modulus of rupture, ovendry

Weight of

filler, ovendry As

received

After

24-hr cold immersion

Sample

cut

length- wise

Sample

cut

cross- wise

Average

Percent

10.5 Percent25.7

Ibjin.i

3, 310

Ib/in.i

3, 945

lb/in.' 3,630lb

7. 16

» Determined in accordance with Federal Specification SS-S-291,

Shingles; Roofing, Cement-Asbestos. The fillers were manufactured by the so- called wet process, in which a revolving cylindrical screen passes through a slurry of asbestos

fiber, Portland cement, and water, picking up a

thin web of the asbestos-cement mixture. The

web is transferred to a wool blanket and carried

to a forming cylinder on wliich successive webs

are collected and compressed until the sheet is the desired thickness. After removal from the

forming cylinder, the built-up sheet, without

further pressing, is cut into blanks of the proper

size and laid on metal forms until sufficiently

cured for handling. The concave face was

smooth and the upper face was covered with

circular depressions, 0.15 in. in diameter and

0.02 in. deep. The asbestos fiber was from

Canada, Russia, and Vermont, mixed in the

proportions which gave satisfactory results.

Figure 3.

Full-sized asbestos-cement filler, floor CT.

[4
The manufacturer refused to divulge the pro- portions of asbestos, cement, and other substances, if any, contained in the fillers. The physical properties of the asbestoscement fillers are given in table 5. Tiio iniiiiu- facturer was the Ruberoid Co.

Asphalt primer.—A mixtin-e of asphalt and

petroleum solvent, containing 50 percent of asphalt, by weight. The asphalt was steamrefined from Mexican Panuco crude petroleum.

The softening point of the asphalt was 110° F by

the ring-and-ball methoti,' and the penetration

I was 60 to 100 at 77° F. The unit of penetration

is one one-hundredth of a centimeter. The

boiling range of the petroleum solvent was 280°

to 420° F. Manufactured by Cities Service

Co. for McBride & Moeller, Inc. Asphalt mastic.—A mixture of asphalt and

latex rubber, containing 10 percent of rubber,

by weight. The asphalt was steam-refined

from Mexican Panuco crude petroleum. The

physical properties of the asphalt were: softening point, 127° to 130° F, by the ring-and-ball

method; 3 penetration,^ 15 to 17 at 32° F (200-g

weight on needle, 60 sec), 45 to 55 at 77° F

(100 g, 5 sec), 220 to 275 at 115° F (50 g, 5 sec).

Manufactured by Cities Service Co. for McBride & Moeller, Inc. Finish flooring.—Wliite oak, identified as Quercus sp. The flooring was of two types, one manufactured in Sweden and the other by

the Kentucky Flooring Co., Orange, Va.

The Swedish flooring was manufactured in

pairs of dovetailed strips, each strip ^2 in. thick by 2^^2 in. face width. The pairs of strips were 16 in. long and were dressed, tongue-andgrooved, and end-matched.

The American flooring was dressed, tongueand-grooved, and end-matched strips, '^Yz2 in. thick by 2% in. face width. The strips were 12

to 20 in. long.

The moisture content of the flooring, determined for 12 strips from each specimen, was

11 percent, based on the weight when dry.

An electric moisture meter was used in the

determination. To calibrate the meter for the

wood in the flooring, two samples of the flooring

from each specimen were dried in an oven at

1 American Society for Testing Materials, ASTM Standard D 36-26.

' American Society for Testing Materials, ASTM Standard D 5-25.

' See footnote 1.

* See footnote 2.

212° F until the weight was constant. Tlie

moistiH-e coriterit was the (liffererice between

the initial weight and the weight when dry,

expressed as a pei-centage of the weight whf^n

dry. The average value was 0.1 greater than

tlie average of tJie corresijonding meter readings.

Therefore, the moisture content was f)l)t ;i iiu'd by adding 0.1 to the average of the meter' leadings and rounding the result to tlie nearest whole nuitd>ei-. Tlie moisture content was

determined on the (hiy the floor specinicn was

tested. Olue.—A mixture of casein and luhber latex. The manufactiu'er refused to divulge further

infonnation. Casein Co. of America, "Casco

Flexible Cement No. 7982."

(h) Dcscriptiori of Specimens

Each specimen of floor CT, shown in figure 4, was 12 ft 8% in. long, 4 ft in. wide, 7^6 in. thick; and consisted of two steel joists, A; hiWsized asbestos-cement fillers, B; half-sized as- bestos-cement fillers, (; concrete, D; asphalt

primer and mastic, E; and white oak finish flooring, F. The price of this construction in Washington,

D. C, as of July 1937, was $0.28/tV.

Joists.—The steel joists, A (fig. 2), were 12 ft 7% in. long, 6 in. deep; spaced 2 ft 0 in. on

centers. The joists were held in position by

temporary wood bracing during the constriiction of the specimens.

Asbestos-cement fillers.—The full-sized as- bestos-cement fillers, R, and the half-sized

fillers, C, rested on the lower fianges. The

outer edges of the half-sized fillers rested on

temporary wood supports. Flat pieces of as- bestos-cement board were placed at the ends

of the specimen, as shown in figure 4, to make

the thickness of the concrete at the ends of

the specimen equal to the depth of the joists. Concrete.—The concrete, D, was 2?^ in. thick

at the crown of the fillers, and was screeded

level Yi to % in. above the upper flanges of the

joists. The concrete for specimens CT-Il and

IS was from batch 1, for specimens 12 and Tl

from batch 2, and for specimens T!i? and T3

from batch 3. After % to 1 hr, the surface of each specimen was dusted with 25 to 30 lb of a mixture of equal parts of portland cement and

sand and then troweled smooth.

[5]
Figure 4.

Floor specimen CT.

A, expanded steel joists; B, full-sized asbestos-cement fillers; C, half-sized asbestos-cement fillers; D, concrete; E, asphalt primer and

mastic; F, finish flooring.

Asphalt primer and mastic.—The primer and

the mastic were appUed by the flooring contractor about 3 weeks after the concrete was

poured. The surface of the concrete was

heated by a blowtorch flame to remove moistm-e

and to raise the temperature to at least 80° F. The primer was heated to 80° to 90° F and

spread, 1 gal/100 ft^, with a brush. It was

allowed to dry for 6 hr or more. Before the

asphalt mastic was applied, the surface of the

primer was heated by a blowtorch flame to at

least 80° F. The mastic was heated to 350°

to 400° F, poured on the floor, and scored by a

rake, which left a corrugated surface. The

quantity of mastic was 4 gal/100 ft '\ and the

thickness was to %i in. Finish flooring.—The flooring was laid several

days after the asphalt mastic was applied.

The surface of the mastic was heated by a blowtorch flame to at least 70° F unmediately

before applying the flooring.

The Swedish flooring was laid as a panel 12

ft long by 4 ft wide, the strips being held to- gether temporarily by cleats nailed across the

panel. The American flooring also was laid as a panel, the strips being joined by casein,

latex glue at the edges and ends and by cleats. These panels were placed on the mastic and

pressed down by a man walking on the surface.

The cleats were then removed. Only five Swedish panels were available, and these were appUed to specimens CT-Tl, T2, II, 12, and

13. The American panel was applied to specimen T3.

(c) Comments

Tilecrete type A floor construction has been

employed in about 700 family units in Virginia,

m 10 homes in Wasliington, D. C, and in 2 business buildings in Westchester County,

N. Y. Both single-family and apartment

buildings have been erected.

[6]
Figure ^.Section of a typical house with

"Tilecrete" floor construction.

A, foundation; B, outside wall; C, partition; D, first floor; E, girder; F, second floor; G, tbird floor: fl, roof;

I, angle clip; J, furring strips.

u1 i: • ~i

-J

A section of a typical house with this floor construction is shown in figure 5. The foundation, A, and the outside walls, B, are of any

accepted load-bearing construction. Partitions,

C, and party walls are of conventional fire-safe design. The first floor, D, is supported by the

foundation and by the steel girder, E. The

second floor, F, and third floor, G, are supported by the outside wall and load-bearing

partition.

The roof, H, also may be of "Tilecrete" construction, and may be either flat or sloping.

Each rafter is connected to a joist of the top

floor by an angle clip, 1. Various types of conventional floor coverings

may be applied. Wood flooring is nailed to sleepers embedded in the concrete or is bonded

to the concrete slab by mastic. Clay tile is grouted to the slab. Ceiling finish is fastened to wood furring

strips, J, secured to the bottom flanges of the

joists. The strips are 1% by 1% by 23% in..

with ends beveled and notched to fit the flanges

of the joists. Either fiberboard or lath is nailed to the furring strips. In basements the

furring strips and ceiling finish may be omitted,

and the lower face of the first floor may be

painted or whitewashed.

On flat roofs, built-up asphalt felt is usually

applied; and on sloping roofs, shingles or tile. Pipes, wires, and conduits are placed in the

spaces enclosed by the asbestos-cement fillers and the ceiling finish. These spaces may be

converted into airtight ducts for air-contlitioning and heating systems by enclosing them with

flat asbestos-cement boards resting on the

lower flanges of the joists. Cross ducts require

special structural details.

2. Transverse Load

Floor specimen GT-Tl under transverse load

is shown in figure 6. The results of the trans- verse load on specimens CT-Tl, T2, and T3

are given m table 6 and m figure 7.

[7]
Figure 6.

Floor specimen CT-Tl

under transverse load.

Table 6.

Structural -properties, floor CT

[Weight, 44.2 Ib/ft^]

Transverse load " Impact load » Concentrated load

Specimen

Maxi- mum

load Specimen

Maxi- mum

height

of drop

Specimen

Maxi- mum

load

Tl Wt'373

332

32.5

11

ft

i> 10.0

b 10.0

b 10.0

PI

lb

b 1, 000

b 1,000

b 1,000 T2 12 P2

T3 IS PS

Average 343 Average b 10.0 Average b 1, 000

» Span 12 ft 0 in. b Test discontinued. Specimen did not fail. Under a load of 300 Ib/ft^ the concrete and

asbestos fillers of specimen CT-Tl cracked

transversely to the joists directly under a loading roller. In specimen T2 under 250 Ib/ft^

two asbestos fillers ruptured under a loading

roller, and under 275 Ib/ft^ the rupture ex- tended completely across the specimen and into

the concrete. In specimen T3 at 250 Ib/ft^ one

filler ruptured under each loading roller, and at

J50

300

zoo I

Sj 150

\

\

100

60

0'

3 J

7

/ •

1

1 «•

1 •

• *

cr 0 0.2 0.4 0.6 0.8 /.o

def/ect/'on in. Figure 7. —Transverse load on floor CT.

Load-deflection (open circles) and load-set (solid circles) results for specimens CT-Tl, T2, and TS on the span 12 ft 0 in.

[8]
Figure 8.

Floor specimen CT-Tl during

the impact test.

def/ecf/on /n. Figure 9.

Impact load on floor CT.

Height of drop-deflection (open circles) and height of drop-set (solid

circles) results for specimens CT-Il, 1$, and IS on the span 12 ft 0 in.

275 lb/ft- the rupture in the fillers e-xtended

completely across the specimen and into the

concrete. In each of the specimens, as the

load was increased further, the transverse cracks in the concrete widened, and others

appeared. Under a load of 373 lb/ft- (maximum

load) on specimen Tl the concrete craclved at the joists longitudinally to the specimen, the

cracks begimiing at one end but not extending

the entire length. Similar cracks occurred in

specimen under 332 Ib/ft^ (maximum load)

and in T3 under 300 Ib/ftl Under the maximum load the deflection of each specimen was

about 3 in., and the cracks in the concrete were

about %6 in. wide.

3. Impact Load

Floor specimen CT-Il during the impact

test is showai m figure 8. The residts of the

impact load on specimens CT-Il, 12, and 13

are given in table 6 and in figure 9.
FiGUKE 10.

Floor tipecitnen CT-Pl under concentrated load. Ring dynamometer shown.

The impact load was applied to the floor specimens on the upper face, the sandbag strik- ing the finish flooruig midway between the

joists. After the 10-ft drop on specimens

CT-Il, 12 and 13, the tests were discontinued,

and the sets were 0.032, 0.037, and 0.031 in., respectively. No other efl'ects were observed.

4. Concentrated Load

Floor specimen CT-Pl under concentrated

load is shown in figure 10. The results of the

concentrated load on specimens CT-Pl, P2,

and PS are given in table 6 and in figure 11. The concentrated load was applied to the

finish flooring midway between the joists,

about 1 ft from the end of the specimen. After

a load of 1,000 lb had been applied the set m

specimen CT-Pl was 0.007 in., in was 0.021

in., and in P3 was 0.016 in., and the tests were

discontinued. There was a slight visible dent in the flooring of specimens P2 and PS, but no

other effects were observed.

indenfaf/on in. Figure 11.

Concentrated load on floor CT.

Load-indentation (open circles) and load-set (solid circles) results for specimens CT-Pl, Pt, and PS.

[101
The description and drawings of the speci- mens were prepared by E. J. Sclicll, G. W.

Sliaw, and T. J. Hanley, of this Bureau's

Building Practice and Specifications Section,

under the supervision of V. B. Phelan.

The structural properties were determined by

the Engineering Meclianics Section, under the

supervision of H. L. Whittemore and A. TT.

Stang, juid tlie Masonry Consduci ion Section,

under the supervision of D. E. Piirsons, with

tl)0 assistance of the following irKinibers of Uu; professional staff: C. C. Fishburn, A. H.Easton,

A. S. Endler, M. Greenspan, A. li. Liinhnni, smd

D. C. List.

Washington, D('.ceni})cr 1], 1939.

o

[11

BUILDING MATERIALS AND STRUCTURES REPORTS

On request, the Superintendent of Documents, U. S. Government Printing Office, Washington,

D. C, will place your name on a special mailing list to receive notices of now reports in this

series as soon as they are issued. There will be no charge for receiving such notices. An alternative method is to deposit with the Superintendent of Documents the sum of $5.00,

with the request that the reports be sent to you as soon as issued, and that the cost thereof be charged against your deposit. This will provide for the mailing of the publications without

delay. You will be notified when the amount of your deposit has become exhausted.

If 100 copies or more of any report are ordered at one time, a discount of 25 percent is allowed. Send all orders and remittances to the Superintendent of Documents, U. S. Government Printing

Office, Washington, D. C.

The following publications in this series are available by purchase from the

Superintendent of Documents at the prices indicated:

BMSl Research on Building Materials and Structures for Use in Low-Cost Housing 10^ BMS2 Methods of Determining the Structural Properties of Low-Cost House Constructions.. 10^ BMS3 Suitability of Fiber Insulating Lath as a Plaster Base 10(i BMS4 Accelerated Aging of Fiber Building Boards 10^ BMS5 Structural Properties of Six Masonry Wall Constructions 15fi BMS6 Survey of Roofing Materials in the Southeastern States 15^ BMS7 Water Permeability of Masonry Walls 10^ BMS8 Methods of Investigation of Surface Treatment for Corrosion Protection of Steel 10^ BMS9 Structural Properties of the Insulated Steel Construction Co.'s "Frameless-Steel" Constructions for Walls, Partitions, Floors, and Roofs 10^ BMSIO Structural Properties of One of the "Keystone Beam Steel Floor" Constructions Sponsored by the H. H. Robertson Co 100 BMSll Structural Properties of the Curren Fabrihome Corporation's "Fabrihome" Constructions for Walls and Partitions 10j5 BMS12 Structural Properties of "Steelox" Constructions for Walls, Partitions, Floors, and Roofs

Sponsored by Steel Buildings, Inc 150 BMS13 Properties of Some Fiber Building Boards of Current Manufacture 100 BMS14 Indentation and Recovery of Low-Cost Floor Coverings 100 BMS15 Structural Properties of "Wheeling Long-Span Steel Floor" Construction Sponsored by

the Wheeling Corrugating Co 100 BMS16 Structural Properties of a "Tilecrete" Floor Construction Sponsored by Tilecrete

Floors, Inc 10^ BMS17 Sound Insulation of Wall and Floor Constructions 100 BMS18 Structural Properties of "Pre-Fab" Constructions for Walls, Partitions, and Floors Sponsored by the Harnischfeger Corporation 100 BMS19 Preparation and Revision of Building Codes 150 BMS20 Structural Properties of "Twachtman" Constructions for Walls and Floors Sponsored by

Connecticut Pre-Cast Buildings Corporation 100 BMS21 Structural Properties of a Concrete-Block Cavity-Wall Construction Sponsored by the National Concrete Masonry Association 100 BMS22 Structural Properties of "Dun-Ti-Stone" Wall Construction Sponsored by the W. E. Dunn Manufacturing Co 10^ BMS23 Structural Properties of a Brick Cavity-Wall Construction Sponsored by the Brick

Manufacturers Association of New York, Inc 100 BMS24 Structural Properties of a Reinforced-Brick Wall Construction and a Brick-Tile CavityWall Construction Sponsored by the Structural Clay Products Institute 100 BMS25 Structural Properties of Conventional Wood-Frame Constructions for Walls, Partitions,

Floors, and Roofs ^^0 BMS26 Structural Properties of "Nelson Pre-Cast Concrete Foundation" Wall Construction

Sponsored by the Nelson Cement Stone Co., Inc 100

[List continued on cover page IV]
BUILDING MATERIALS AND STRUCTURES REPORTS

[Continued from cover page III]

BMS27 Structural Properties of "Bender Steel Home" Wall Construction Sponsored by The

Bender Body Co 10^ BMS28 Backflow Prevention in Over-Rim Water Supplies iq^

BMS29 Survey of Roofing Materials in the Northeastern States 10^ BMS30 Structural Properties of a Wood-Frame Wall Construction Sponsored by the Douglas

Fir Plywood Association iq^

BMS31 Structural Properties of "Insuiite" Wall and "Insulite" Partition Constructions Sponsored by The Insulite Co 15jt BMS32 Structural Properties of Two Brick-Concrete-Block Wall Constructions and a Concrete- Block Wall Construction Sponsored by the National Concrete Masonry Association. lOjt BMS33 Plastic Calking Materials 10(4 BMS34 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 1 lOjS BMS35 Stability of Sheathing Papers as Determined by Accelerated Aging iq^

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 lOjt BMS38 Structural Properties of Two "Dunstone" Wall Constructions Sponsored by the W. E. Dunn Manufacturing Co 100 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 100 BMS41 Effect of Heating and Cooling on the Permeability of Masonry Walls 100 BMS42 Structural Properties of Wood-Frame Wall and Partition Constructions with "Celotex"

Insulating Boards Sponsored by the Celotex Corporation 100 BMS43 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 2 100 BMS44 Surface Treatment of Steel Prior to Painting 100 BMS45 Air Infiltration Through Windows 100 BMS46 Structural Properties of "Scot-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 ' 100 BMS48 Structural Properties of "Precision-Built" Frame Wall and Partition Constructions

Sponsored by the Homasote Co 100 BMS49 Metallic Roofing for Low-Cost House Construction 100 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



i