la! Bureau of Standards. •.
BUILDING MATERIALS AND STRUCTURES REPORTS

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BMSl Research on Building Materials and Structures for Use in Low-Cost Housing I0<i BMS2 Methods of Determining the Structural Properties of Low-Cost House Constructions" lOrf BMS3 Suitability of Fiber Insulating Lath as a Plaster Base \\ lOrf BMS4 Accelerated Aging of Fiber Building Boards !.'.*.'.*!!!.'!!!!!! lOrf BMS5 Structural Properties of Six Masonry Wall Constructions 15$ BMS6 Survey of Rooting Materials in the Southeastern States !...'!!!!!.*!!!!!! 15rf BMS7 Water Permeability of Masonry Walls .*.".'.*.*.*.'.*.*.'.'.*.'.* (*) BMS8 Methods of Investigation of Surface Treatment for Corrosion Protection of'steelV.V.V. lOrf 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 10^ BMSll Structural Properties of the Curren Fabrihome Corporation's "Fabrihome" Constructions for Walls and Partitions 10^ BMS12 Structural Properties of "Steelox" Constructions for Walls, Partitions, Floors, and

Roofs Sponsored by Steel Buildings, Inc 15^ BMS13 Properties of Some Fiber Building Boards of Current Manufacture 10^ BMS14 Indentation and Recovery of Low-Cost Floor Coverings 10^ BMS15 Structural Properties of "Wheeling Long-Span Steel Floor" Construction Sponsored by

the Wheeling Corrugating Co 10^ BMS16 Structural Properties of a "Tilecrete" Floor Construction Sponsored by Tilecrete

Floors, Inc 10^ BMS17 Sound Insulation of Wall and Floor Constructions 20^ Supplement to BMS 17, Sound Insulation of Wall and Floor Constructions 5^ BMS18 Structural Properties of "Pre-Fab" Constructions for Walls, Partitions, and Floors Sponsored by the Harnischfeger Corporation 10^ BMS19 Preparation and Revision of Building Codes 15<( BMS20 Structural Properties of "Twachtman" Constructions for Walls and Floors Sponsored

by Connecticut Pre-Cast Buildings Corporation 10^ BMS21 Structural Properties of a Concrete-Block Cavity-Wall Construction Sponsored by the National Concrete Masonry Association 10^ 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 10^ BMS24 Structural Properties of a Reinforced-Brick Wall Construction and a Brick-Tile CavityWall Construction Sponsored by the Structural Clay Products Institute 10<f BMS25 Structural Properties of Conventional Wood-Frame Constructions for Walls, Partitions,

Floors, and Roofs 15^ BMS26 Structural Properties of "Nelson Pre-Cast Concrete Foundation" Wall Construction

Sponsored by the Nelson Cement Stone Co., Inc , 10<j; BMS27 Structural Properties of "Bender Steel Home" Wall Construction Sponsored by the Bender Body Co 10^ BMS28 Backflow Prevention in Over-Rim Water Supplies lO^j 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 10^ BMS31 Structural Properties of "Insulite" Wall and "Insulite" Partition Constructions Sponsored by The Insulite Co 15«( [List continued on cover page lu]

* Out of print.
UNITED STATES DEPARTMENT OF COMMERCE . Henry A. Wallace, Secretary

NATIONAL BUREAU OF STANDARDS . Lyman J. Briggs, Director

BUILDING MATERIALS

and STRUCTURES

REPORT BMS104

Structural Properties of Prefabricated Plywood Lightweight Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by the Douglas Fir Plywood Association

by ARNOLD WEXLER, SANFORD B. NEWMAN, and VINCENT B. PHELAN

xoith the collaboration of

R. r. LUXFORD

Forest Products Laboratory

Forest Service, United States Department of Agriculture

ISSUED NOVEMBER 1, 1945

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 . 1945

FOB SALE BY THE SUPEKINTENDENT OF DOCUMENTS, U. S. GOVERNMENT PRINTING OFFICE WASHINGTON 25, D. C. . PRICE 25 CENTS
Foreword

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

structural properties of constructions intended for lo'.v-cost houses and apartments.

These constructions were originally sponsored by an organization within the building

industry advocating and promoting their use and subsequently by the National Housing

Agenc}' seeking improvements in house constructions. The sponsor built and submitted

the specimens described in this report for participation in the program outlined in Building INIaterials and Structures Report BMS2, Methods of Determining the Structural Properties of Low-Cost House Constructions. The sponsor, therefore, is responsible for the design of the constructions and for the description of materials and

metliod of fabrication. The Bureau is responsible for the testing of the specimens and

preparation of the report.

This report covers the load-deformation relations and strength of the elements when

subjected to compressive, transverse, concentrated, impact, and racking loads by

standardized methods simulating the loads to v^-hich the elements would be subjected

in actual service.

The National Bureau of Standards does not "approve" a construction nor does it express an opinion as to its merits for reasons given in reports BMSl and BMS2. The

technical facts presented in this series provide the basic data from Avhicli architects and

engineers can determine whether a construction meets desired performance requirements.

Ltman J. Briggs, Director.

[n]
Structural Properties of Prefabricated Plywood Lightweight Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by the Douglas Fir Plywood Association

by ARNOLD WEXLER, SANFORD B. NEWMAN, and VINCENT B. PHELAN

with the coJlahoratlon of

li. ¥. i.uxFtmu

Forest Products Laboratory, Forest Service, United States Department of Agriculture

CON

Page Foreword H

[ntroductiou Part 1. Lightweight coustructioii -

I. Sponsor and product 2

II. Specimens and tests 2

III. Materials 4

1. Wood 4

(a) Framing 4

(b) Plywood, moisture-resistant type 5

(c) Plywood, exterior type .... o

2. Nails 7

3. Glue 7 IV. Wall DV 7

1. Sponsor's statement 7 (a) Four-toot wall specimens..

(b) Eight-foot wall specimens. . 10

(c) Comments tO

2. Compressive load 11

3. Transverse load 13

4. Concentrated load 15

5. Impact load 16

6. Racking load 16

V. Partition DW 17

1. Sponsor's statement 17 (a) Pour-foot partition speci- mens 17

(b) l^ight-foot partition speci- mens IS

(c) Comments 18

2. Compressive load IS

3. Transverse load 20

4. Concentrated load 20

5. Impact load 21

6. Racking load 22

VI. Floor DX 22

1. Sponsor's statement 22

(a) Description of specimens .. 28

2. Transverse load 23

3. Concentrated load 24

4. Impact load 24

VII. Floor DY 24

1. Sponsor's .slatenieni -4

(a) Description of specimens . . 2.5 2. Transverse load 26

3. Concentrated load 27

4. Impact load 27

VIII. Floor DYn 29

1. Si)()nsor's stateuient 29

(a) Description of specimens .. 29

(b) Comments 29

2. Transverse load 29

TENTS

Page

IX. Root 1)'/, 30

1. Sponsor's statement 30

(a) I »«>scrii)tion of specimens'.. 30

2. Transverse load 31

3. Concentrated load 31 X. Roof D7m 32

1. Sponsor's statement 32

(a) Description of specimens .. 32

(b) Comments 32

2. Transverse load 33

XI. Additional connrients by sponsor 34

Part 2. Commercial type construction 34

I. Sponsor and product 34

II. Specimens and tests 34

III. Materials 3.5

1. Wood 35

(a) Fi'aniinf;- 3.5 (b) Plywodd 35

(c) Furring 36

(d) Bevel siding 36

2. Slieatbing paper 36

3. Nails 86

4. Staples 36

5. (Jlue 38

(j. I'aint 38

IV. Wall EA 38

1. Sponsor's statement 38

(a) Four-ftjot wall specimens .. 38

(b) Eight-foot wall .specimens.. 39

2. Laboratory statement 40

3. Compress! v(! load 40

4. Transverse load 41

5. Concentratetl ]o;id 42

6. Impact Iliad 43

7. Racking lead 44

V. Wall EAa 45

1. Sponfsor's statement 45

(a) Description of specimens . . 45

2. Racking load 45

VI. Wall EAh 45

1. Sponsor's statement 45

(a) Description of specimens .. 45

(b) Comments 46

2. Racking load 47

VII. Additional connnents by sponsor 47

[1]
.M'.STRACT

For the program ou the determinatiou of structural properties of low-cost house constructions, tlie Doujrlas Fir Plywood Association subuiitted 75 specimens

representing prefabricated plywood building panels of both lightweight stress-skin and commercial design.

Wall, partition, floor, and roof specimens were of lightweight stress-skin design. Specimens of commercial type panels (2- by 4-in. studs) were for wall con- struction only, and furnislied a basis of <-(>mparison of strength and weii;lir with the light weight constructions. The wall specimens were subjected to cnujpressive. transvessel 'concentrated, impact, and racking loads: and the wall specimens of commercial type included

three different constructions for determining resist- ance to racking. The partition .specimens were sub-

.jected to compressive, transverse, impact, and racking

loads ; the tloor specimens to transverse, concentrated,

and impact loads : and the roof specimens to trans- verse and concentrated loads. The floor and roof

specirmens included two dill'erent constructions for determining resistance to transverse loads. Transverse, concentrated, and impact loads were applied to both faces of wall specimens. The loads simulated

the loads to which the elements are sub.iected in actual

service. The deflection under load and the sets after the load was removed were measured for uniform increments

of load. The results ;ire presented in graphs and

tables.

IXTROOUCTION

To provide teclinical facts on the performance of constructions for low-cost houses, to discover promising new constructions, and uhimatel_>' to determine the properties necessaiT

for acceptable performance in actual service,

the National Bureau of Standards has invited

the cooperation of the building industry in a program of researcli on building materials and

structures suitable for low-cost houses and

apartments. The objectives of this program

are described in Building Materials and Structures Report BMSl, Research on Building Materials and Structures for Use in Low-Cost

Housing.

To determine the strength of house constructions in the laboratory, standardized methods

were developed for applying loads to portions

of a completed house. Included in this study were masonry and wood constructions of

types that have been used extensively foi- houses in this country. The reaction of these

constructions under widely different service

conditions is well known to builders and to the

public. The BIMS Reports on these constructions are BMS5, Structural Properties of Six

Masonr}' Wall Cotistructions, and BAfS25,

Structural Properties of Conventional WoodFrame Constructions for Wnlls, Partitions,

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

The present report describes the .structural properties of wall, partition, floor, and roof

constructions sponsored by an association of

manufacturers in the building industry.

The wall specimens were tested for resistance

to com})ressive, transverse, concentrated, impact, and racking loads simulating the loads to Avhich the Avails of a house are subjected. In

actual service, compressive loads on a wall or load-bearing partition are produced by the

v.eight of the roof, second floor and second

story walls, if any, by furniture and occupants,

and by snow and wind loads on the roof.

Transverse loads are produced by wind; con- centrated and impact loads by accidental contact with heavy objects; and racking loads by

the action of the wind on adjoining walls. Partition specimens were tested for resist- ance to compressive, transverse, impact, and

racking loads. Causes of such loads on partitions are the same as for walls. Floor specimens were tested for resistance to

1 ransverse, concentrated, and impact loads. Transverse loads are applied to floors by furni- ture and occupants ; concentrated loads by furriiture, for example the legs of a piano; and

impact loads by objects falling on the floor or by persons jumping on the floor. Roof specimens were tested for resistance to transverse and concentrated loads. Transverse

loads are applied to roofs by wind and snow;

concentrated loads by persons walking on the

roof, and by tools and equipment laid on the

roof while it is being constructed or repaired.

The deflection and set under each increment

of load were measured, because the suitability

of a construction depends not only on its resist- ance to deformation wlien loads are applied but

also on its abilitj^ to return to its original size

and shape when the loads are removed.

[2]
PART 1. LIGHTWEIGHT CONSTRUCTION

I. SPONSOR AND PRODUCT

The specimens were submitted by the Douglas Fir Plywood Association, Tacoma, Wash.,

and were built by the Evans Products Co.,

Marshfield, Ore., manufacturers of prefabricated houses emj)loying Douglas fir plywood in their products. Each of the constructions consisted of a lightweight wood frame and faces of

Douglas fir plywood. The faces were securely

glued to the frames, so that each consti'uction

acted as a unit when resisting load. Buildings

in which these constructions are used are designed to be erected on conventional masonry

foundations, the panels joined by wood splines.

II. SPECIMENS AND TESTS

The specimens represented four elements of a house and were assigned the following symbols: Wall, DV; partition, DW; floor, speci- mens of 8-ft 0-in. length. DX; floor, specimens

of 12-ft 6-in. length and ceiling face buttjointed, DT ; floor, specimens of 12-ft 6-in. length and ceiling face scarf-jointed. DYa:

roof, specimens of 12-ft 6-in. length and ceil- ing face butt-jointed, DZ; roof, specimens of

12-ft 6-in. length and ceiling face scarf-jointed,

DZa. The individual specimens were assigned

the designations given in table 1. Table 1

.

Specimen designations

Con- Element 3trvirtion Specimen Load Load

symbol designation applied

Wall DV CI , C2, C3 Compressive.

.

Upper end. Do DV Tl T2 T3 Transverse Inside face. Do DV Til, Ts] T6 do Outside face. Do DV P1,P2.P3 Concentrated _ Inside face. Do DV P4,Po,P6 do Outside face.

- -^Do DV 11,12. IS Impact" Inside face. Do DV U, 13. 16 do Outside face. Do DV R1,R2,R3 Racking Near upper end.

Partition DW ci.cs, CS Compressive.

.

Upper end.

. Do DW T1,T2, TS Transverse Either face.

_ -Do DW P1,P2, PS Concentrated _ Do. Do DW 11 , 12, IS Impact" Do. Do DW R1,R2,R3 Racking Near upper end.

Floor- DX Tl , T2, TS Transverse Upper face. Do DX P1,P2.P3 Concentrated _ Do. Do DX 11, 12, IS Impact" , Do. Do DY Tl , T2, TS Transverse^ _ _ Do. Do DY P1,P2,PS Concentrated

.

Do. Do DY 11, 12, IS Impact Do. Do DYa Tl , T2, TS Transverse Do. Roof DZ Tl, T2, TS Transverse'' .. Do. Do DZ P1,P2,P3 Concentrated _ Do. Do DZa Tl,T2, TS Transverse Do.

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

specimens, transverse loads first. Specimens were tested in accordance with

BMS2 except where indicated to the contrary.

That report also gives the requirements for the

specimens and describes the results of tests by

means of figures, particularly load-deformation

graphs.

Because the shortening of the entire specimen under compressive load may not be proportional to the values obtained from compressometers attached to the specimen over only a portion of its height, the shortenings and tlie sets were measured with compressometers at- tached to the steel plate through which the load was applied, not attached to the specimen as described in BMS2.

The lateral deflections under compressive

loads were measured with a deflectometer of

fixed gage length, Avhich consisted of a light

(Duralumin) tubular frame having a leg at one end and a hinged plate at the other. The

deflectometer in a vertical position was at- tached to the specimen by clamping the hinged

I^late near the upper end to one of the faces. The gage length (distance between the points

of support) was 7 ft 6 in. A dial micrometer was mounted on the frame at midlength, with

the spindle in contact with the wall or partition specimen. The dial was graduated to

O.OOl in., and the readings were recorded to the

nearest division. There were two deflectometers on the specimen, one near each outer stud.

This method of measurement was used instead

of the taut-wire mirror scale method described

in BMS2.

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 steel disk. A, to which the cross bar, B, was rigidly :it- tached. The load was measured by means of

the dynamometer, C Two stands, Z>, rested on

the face of the specimen, each supporting a dial

micrometer, E, the spindle of which was in contact with the cross bar 8 in. from the center of the disk. The micrometers were graduated

to 0.001 in., and readings were recorded to the nearest division. The initial reading

(average of the micrometer readings) was observed under the initial load, which included

the weight of the disk and dynamometer. A

load was applied to the disk, and the average

of these micrometer readings minus the initial reading was taken as the depth of the indentation under load.

The deflections and the sets under the impact

load were measured by means of two deflectometers and two set gages, not one of each, as described in BMS2. The deflectometers were

placed in contact with the unloaded face of the

[3]
speciineii at iiii(ls[)iiii. one under eaeli niiit'r longitudinal member, and. the set gages rested on the loaded face, one over eacli inner longitudinal member. The readings, therefore, were

not allected by local deformations of the faces. The deformations under racking loads were measured with a rigid angle deformeter consisting of a steel channel and a steel angle

braced to form a rigid connection. The channel

of the deformeter rested on two steel plates, i

by -f in., y.i in. thick, and was fastened to the

top of the specimen by two }iails extending into

the top plate, the steel angle extending downward in the plane of the specimen. The bottom

plate was in contact with the stop, to which a

dial micrometer spindle was attached. The

micrometer spindle was in contact with the

steel angle of the deformeter. The gage length

(distance from the top of the specimen to the

spindle) was 7 ft 11% in. The micrometer was

graduated to 0.001 in., and the readings were

recorded to the nearest division. The deformeter was used instead of the taut -wire mirrorscale device described in BMS2.

Only three of the load-bearing partition

specimens, DW, were tested under the transverse, concentrated, and impact loads, not six

specimens, as stated in BMS2. Inasmuch as the load-bearing partition construction was

S3'mmetrical about a i:)lane midway between

the faces, the results for these loads applied to one face of the specimens should be identical

with those obtained by applying the loads to the other face. The floor specimens, DX, were 8 ft long, the

length of commercial panels, and not 12 ft 6 in. long as described in BMS2. The transverse and impact tests of the DX specimens were,

therefore, made on a ?,piin of 7 ft 6 in. The roof specimens, DZ, were 12 ft 6 in. long,

the length of commercial panels, and not 14 ft. 6 in. long as described in BMS2. The trans- verse tests of the DZ specimens were, therefore, made on a span of 12 ft. Because there was no reason to believe that

the design of the splice in the lower plyAvood

face would affect the concentrated load i^roperties of the floor specimens, DY, and because

Figure l.—Wall specimen EA-P/f under concentrated load.

A, Sfeel loading disU : /.'. cidss bar; C. dynaraomPter ; D. stand; E. dial micrometer.

[4]
they had not failed in the impact load test for

a height-of-drop of 10 ft, the DTa specimens were subjected only to transverse loads. As it was improbable that the design of the

splice in the lower plywood face would atfect the concentrated load strength of the roof

specimens DZ, the DZa specimens were subjected only to transverse loads. The tests were begun May 24, 1943, and completed August 28, 1943. A stall' member of the

Forest Products Laboratory witnessed the

tests, and the sponsor's representative witnessed some of the tests.

III. MATEEIALS

Information on the materials was obtained

from the sponsor and by inspection of the

specimens. The Forest Products Laboratory

assisted by identifying the species of wood and

the Engineering Mechanics Section of the National Bureau of Standards assisted by determining the moisture content of the wood.

1. W.H)1)

{a) Framing

Although the sponsor stated that the framing was Douglas lir. No. 1, common, when the

faces were removed it was observed that in the

walls having 1- by 3-in. studs there were knots

only in a very few of the specimens. These

studs, therefore, were clear stock.

^%2 by 21/2 in. (nominal 1 by 3 in.)

by 31/2 in. (nominal 1 by 4 in.)

by 53/2 in. (nominal 1 by 6 in.)

IV2 by 21/2 in. (nominal 2 by 3 in.)

1% by 1% in. (nominal 2 by 2 in.)

(b) Plyioood, 21oistu re-Resistant Type

Douglas fir, i/j-in., %-in., and 1/2-in., bonded

with water-resistant protein glue having a

soya-bean and casein base. The i/4-in. plywood

was 3 ply, Avallboard grade, sanded, and complied with the requirements of Douglas Fir

Plywood Association "Plywall." The %-in.

FiGUKis 2.— ivaa D\.

Typical 4-foot specimen.

[5]

plywood was ply sheathing grade, and complied with Douglas Fir Plywood Association

"Plyscord." The Vo-in. plywood was 5 ply

wallhoard grade, sanded, and complied with

Douglas Fir Plywood Association "Plywall.''

All plywood complied with Commercial Standard 0845-42.

(c) PJi/iCooJ, Exterior Type

Douglas fir, and %-in., bonded with

hot-press synthetic-resin adhesive, 3 ply, grade

S2S (sound two sides). The plywood complied

with Commercial Standard CS45-42 and was marked "Ext.-D.F.P.A."

After each specimen was tested, one face was

removed to expose the framing, and samples of

framing and plywood were cut for moisturecontent determination and for identilication of

the species. Figures 2 to 8. inclusive, are

typical specimens.

Samples of plywood and framing were taken

from each specimen on the day the specimeii was tested; they were weighed and then dried

to constant weight in an oven at 212° F. The

moisture content, given in table 2, was calculated on the oven-drv weight.

Ta)ilk 2.

Mointure content of the wood

|l)< l(!rmined on the day the wall, partition, Hoor, or roof epcciinen wan tPHtcfll

Wood

Half Bplinc.

I'raniing.

Dougla.'S fir plywood, 14-"'-

Douglas fir plywood, iii-in_

Douglas fir plywood,

Douglas fir plywood, 3^-iu_

Moisture content Construction

lyrabol

DV

DW

DX

DY

DYa DZ

DZa DV

DW

DX

DY

DYa

DZ

DZa DV

DW

DZ

DZa DX

DY

DYa DV

DZ

DZa DX

DY

DYa

Minin)ijra

Percent

10

10

10

9

010

9

910

9

9108

10

Maxi- mum

Percent

12

12

12

11

1

1

1

1

1

1

12

12

1112

11

11

J 11

9

10

9

Avfrage

Percejit

1

1

U

1

1

10

)'l

1 1 10

11

1110

1

1

1110

10

Figure 5.

Partition DW.

Typical 8-foot specimen.

\7]
181
FiGUEE 8.—Roof DZ.

Typical specimen.

2. Nails

All nails were steel wire nails and are described in table 3. Table 3.

Description of 7iails

Steel Nails Typo Size Length wire Diam- Finish per gage eter pound

Pennu in. No. in. Box "3 IM 14M 0.076 Briglit C35 Do 4 1^ 15 .072 --_dO-- 5t4 Do 6 2 12K .0985 23.3 Common 8 Wii .131 106

Finishing. _ 3 iM 15>i .0673 _-_do-- 807 Do 4 15 .072 _..do-. 584

» Duckbill point. 3^ Glue

Casein glue, grade A, ground. Formula:

casein, 65 percent; lime, 15 percent; and dis- persing agents and undisclosed ingredients,

20 percent. Eleven parts of glue were mixed

with 211^ parts of water by weight. I. F.

Laucks, Inc., "Lauxein 888."

IV. WALLZ>F

1. Sponsor's Statement

"Wall DV was a lightweight wood frame

with plywood as both faces, the faces being

fastened by glue. The faces were subjected to a .pressure of 86 lb/in.- on surfaces of the frame

for a period of 35 minutes, while the glue hardened. To hasten the time of set, the temperatui-e of air surrounding w^ork in the presses was raised to 141° F by panels of infrared

light. The specimens were not painted.

The price of this construction in "Washington, D. C, as of July 1937 was $0.24/ft^.

{a) Four-Foot Wall Specimens

The 4-ft wall specimens, shown in figure 9, were 8 ft 0 in. high, 3 ft 11% in. wide, and 31^

in. thick. Each was a wood frame to which

the faces were fastened. The frame consisted

of four studs. A, fastened to transverse members, B, at top and bottom. There were two

lines of blocks, C\ extending between the studs.

Outside face, D, and inside face, F, each consisted of one piece of plywood. Plates, F, ex- tended across the top and bottom ends of the

specimens, and half splines, G, were inserted

between the faces at tlie sides. Studs.—The studs. A, were Douglas fir, _2%2 by 21/2 in. (nominal 1 by 3 in.) 7 ft 71/2 in. long, spaced 1 ft 3 in. on centers. Transverse memhers.—The transverse members, Z?, were Douglas fir, by 2i/^ in. (nominal 1 by 3 in.) 3 ft IQi/i in. long," extending

across the ends of the studs. The transvei-se

members were fastened to the studs by 6d box

nails driven through the transverse membei's

into the ends of the studs, two nails into each

stud end.

Blocks.—Blocks, C, were Douirlas fir, by 21/2 in. (nominal 1 by 3 in.)' 1 ft 214 in. long, inserted between the studs in two lines

about equidistant from the transverse members

and each other. The blocks were fastened to the studs by 6d box nails. Two nails were

[9]
FiGUKE 9.

Four-foot icall specimen DV.

A . Stud ; B, transverse member ; C, block ; D, outside face

;

E, inside face ; F, plate ; Cr, half spline.

driven through the outer studs into the ends

of the outer blocks and one nail through the

inner studs. The inner block was fastened by

nails toenailed through the inner studs, one

nail toenailed through each stud.

Outside face.—The outside face, Z>, was one

piece of Douglas fir plywood, exterior type, %

in. thick, 8 ft 0 in. long, and 3 ft 1134 in. wide.

It was fastened by glue to all the frame ineni- bers, which had been coated with the glue mixture.

Inside face.—The inside face, E., was one

piece of Douglas fir plywood, moisture-resistant type, 14 in. thick, 8 ft 0 in. long, and 3 ft 11% in. wide. It was fastened by glue to all the frame members, which had been coated

with the glue mixture.

Plates.—Both fioor and top plates, F,, were Douglas fir, V/o by 21/2 in. (nominal 2 by 3 in.)

3 ft. 11% in. long. The plates were inserted

between the faces of the specimens after the

faces had been attached to the frames and were

fastened in place by Gd box nails driven

through the faces and spaced approximately

6 in. apart. There were also three 8d common

nails driven througli each plate into the trans- verse member, spaced about halfway between

the studs. In some specimens, glue had been

partially applied to the sides of the plates, but

in other cases this was omitted.

Half splines.—Half splines, G, were Douglas

fii"- ~%2 by 21/2 in. (nominal 1 by 3 in.) 7 ft 9 in. long. The half splines were inserted between the faces of the sj^ecimens after the faces

had been attached to the frames, and were fast- ened in place by 6d box nails driven through

the faces and spaced approximately 6 in. apart.

In some specimens, glue had been partially

applied to the sides of the half splines, but in

other cases this was omitted.

(&) Eight-Foot IVaJl Speci7n,ens

The 8-ft wall specimens, shown in figure 10, were 8 ft 0 in. high, 7 ft ll^/o in. wide, and 3V8

in. thick. The specimens consisted of two 4-ft

panels like the 4-ft specimens, joined together

and held in place by continuous plates, at top and bottom; and full size spline, //, between the specimens.

Plates.—Plates, F^ were similar to those for

the 4-ft specimens, but Avere 7 ft llVo in. long,

and fastened in a similar manner.

Spline.—Spline, 77, was Douglas fir, fi/o by

21/0 in. (nominal 2 by 3 in.) 7 ft 9 in. long. The

spline was inserted between the faces of the

adjoining panels, and the panels fastened by 6d

box nails driven through the faces into the

spline along the adjacent edges, sjiaced

approximately 6 in. aj^art.

(c) Comments

The outside walls of a house consist of panels

similar to the 4-ft specimens. The panels rest on the floor, and are joined together and held

in place by continuous plates at top and bottom

and full-size wood splines between them as rep- resented by the construction of the 8-ft speci- mens. Openings for doors and windows are provided by specially constructed panels. The

outside and inside surfaces of this construction

are usually finished with paint.

[10]
2. Compressive Load

Wall specimen DV-CI, luuler compressive

load, is shown in fig-ure 11. The test results for

wall specimens D]'-Cl, C'3, and CJ, are shown

in table -4 and figures 12 and 13. The compressive loads were applied 1.02 in. (one-third tlie thickness of the panel) from the inside face of

the panel.

[H]
Table 4.

Structural properties of loall DV

[VciTht, based on face area: 2.96 lb/ft']

Conipressivo load'^ Transverse load; span, ! 7 ft C, i-i. , Concentrated load; disk, diam 1 in. Impact load; span,

7 ft 6 in.; sandbag, 60 lb Racking load

Specimen Maximum

load Specimen Maximum

load Specimen Maximumload Specimen Maximumload Specimen Maximum

load

CI..

Kips/fl^ 8.20

10.87 12.58

Tl Wft'

257

284

309

PI

Ih 700

655

500

/( 7 5 7'0 8.0 m

Kips/ft^ 1.S3 2.35

1.43

C'2 P2 J2 C3 T3 PS 13 RS

Average 10.37 Average 283 Average 618 Average 7.5 Average 1.87

T4. 309 268

329

PA =1,000 885 900

14 «10.0

clO.O =10.0 To Lo T6 p.. 16 Average 30J xiverage Average 10.0

<^ Load applied 1.02 in. ('a the thickness of the panel) from the inside face.

b A kip is 1 ,000 lb.

= Test discontinued. No failure.

to

Co

to

I<0

5

4

3

0

•

1 • —^ c

o

1

1

CI

y-f—o

o

^9

1»

1

1•

1»- —o—d>

•

1 /

»

1 <rf y r

A, Compre-ssometer ; B, deflectometer.

O .05 .10 .15

shorfeninq in.

Figure 12.

Compressive load on wall DV.

Lond-sliortening (open circles) and load-set (solid circles) ifsulfs for specimens DV-Cl, C2, CS. The load was applied 1.02 in. (one-third of the thickness of the panel) from the inside face. The loads are in kips per foot of actual width of specimen.

The shortenings and sets shown in figure 12

for a height of 8 ft were obtained from the

compressometer readings. The compressometei's were attached to the plates through which

[12]
the load was applied ; the gage length was 8 ft. The lateral deflections jDlotted in flgure 13 are

deflections toward the outside face of the

panels.

6»

-1^

1

I

5

4"

3

2'

0

1

o

m oo

» O 1

1 o

^

1 °

7 °

O

t o p o

Jno

7

0 .05 JO

/a feral defleciion in,

FiGTJKE 13.

Compressive load on wall DV.

lioad-lateral deflection (open circles) and load-lateral set

(solid circles) results for specimens DV-Cl, C2. C3. The

load was applied 1.02 in. (one-third of the thiclcness of the panel) from the inside face. The loads are in kips per foot of actual width of specimen. The deflections and

sets are for a gage length of 7 ft 6 in., the gage length

of the deflectometers.

tively, the inside face separated from the

spline. Under tlie maximum load, there was a compression failure of the inside face of specimen 02 and splitting of the spline near the top

of the i^anel of specimen 03.

The speed of the movable head of the testing

machine was adjusted to 0.072 in./min.

Specimen 02 under a compressive load of 5.0 kips/ft is shown in figure 14. The buckles between the studs are visible on the inside plywood face of the wall.

At a load of 4.25 and 6.48 kips/ft for speci- mens 01 and 03, respectively, loud noises were

heard, probably caused by the failure of glue

joints. At a load of 4.35, 6.92, and 6.48 kips/ft

for specimens OJ, 02, and 03, respectively,

crushing occurred under the top plate at the

end of the studs. At a load of 5.53, 3.50 and

6.49 kips/ft for specimens 01, 02, and 03,

respectively, the inside face of the panel started

*' to buckle. At a load of 7.92, 10.87, and 12.17

kips/ft for specimens 01, 02, and 03, respecFiGUEE 14. —Wall specimen J)V-C2 under a compressive load of 5.0 kips/ft. Note the buckles in the inside plywood face of the wall.

Figure 15 shows the separation of the plywood inside face of specimen 01 from the studs

after the maximum load had been reached.

3. Transverse Load

The results of the transverse-load test are shown in table 4 and in figure 16 for wall speci- mens DV-Tl, T2, and To, loaded on the inside

face, and in figure 17 for specimens DV-TI),, T5^

and T6, loaded on the outside face.

[13]
r

Kniuiiii 1.). — W nil aijcciinen DV-Gl after titc iHu.rittuuii compressive load had been reached.

200

deflection in. Figure 16.

Transverse load on wall DV, load applied

to inside face.

Load-deflection (open circles) and load-set (solid circles) results for specimens DV-Tl, T2, and T3 on the span 7

ft 6 in. The load (pounds per square foot) is the total load divided by the product of the span and the width

of the specimen.

The speed of the movable head of tlie testing

machine was adjusted to 0.1G5 in./min.

The transA^erse loads were applied to the in- side face of specimens DT-2'1, and I'J. F.;r specimens Tl, T£, and T3, respectively, the

inside face be<?:an to buckle between the loading

rollers at a load of 140, 100, and 140 Ib/ft^;

loud noises, probably caused by tlie failure of

glue joints, Avere f:rst hsard at a load of 149,

183, and 205 lb/ft-; and the inside face began

to separate from the half splines at a load of

257, 253, and 308 Ib/ft^. On specimen T:2, the

plywood on the inside face split near the lialf splines at a load of 262 Ib/ft^ and one half

sjoline broke in tension at a imot at a load of

274 Ib/ft^. Under the maximum load, a half

spline in each specimen failed in tension. Examination of the specimens after test disclosed

horizontal shear failures in an inner and an

end stud of Tl, compressive failures in tAvo inner studs and one outer stud of T3, and compressive failures in four studs of T3.

The transA'^erse loads were applied to the outside face of specimens BV-T^., 7"5, and T6. For

specimen T4, loud noises were heard at a load

of 135 lb/ft-, and continued to be heard until

the test was discontinued, apparently indicating the failure of glue joints. At 157 Ib/ft^

the outside face began to buckle betAveen

rollers. At 271 Ib/ft^ the inside face failed in

tension under one loading roller. The inside

plywood buckled at 303 lb/ft2. One spline

failed in tension at 306 Ih/ft-. Examination

after test showed that one inner stud had failed

in compression. For specimen T5, the loud

noises Avere first heard at a load of 157 lb/ft-.

The outside plyAvood began to buckle at 180

lb/ft-, and the inside plyAvood began to buckle

at 219 lb/ft-. Tensile cracks appeared in the

inside plywood at 246 lb/ft- and 251 Ib/ft^ near midspan. Examination after test disclosed a

horizontal shear failure in one stud. On specimen T6, the outside plywood began to buckle

at 160 lb/ft-, and loud noises were first heard

at 315 Ib/ft^. Under the maximum load, one

[14]
spline failed in horizontal shear and in tension.

Examination after test disclosed compressive

failures in three studs and horizontal shear

failures in two studs.

200 \

^/50

I

50 \

0

Oydo

e

1

G

•

1•

1

1p

i0h-

/

lL® o \J DV-4 0 0.2 0.4 0.6 o.a

defleciion in, Figure 17.

Transverse load on wall DV, load appl'.cd

to outside face.

T/oad-deflection (open circles) and load-set (solid circles) results for specimens DV-T.if, T5, and T6 on the span 7

ft () in. The load (pounds per square foot) is the total load divided by the product of the span and the width

of the spccinioii.

4. Concentrated Load

The results of tlie concentrated-load test are shown in table 4 and in figure 18 for wall speci- mens DV-Pl, and Pj\ loaded on the inside

face, and in figure 19 for wall specimens

D V-P/^, P.5, and PC, loaded on the outside face. The concentrated load was applied to speci- mens DV-Ph P'B, and PS midway between two

of the studs and I6I/2 in. from one end. Each

of the specimens DV-Pl, PS, and P3 failed by

the disk punching through the plywood.

The concentrated load was applied to specimen DV-P/^ midway between two of the studs

and I5I/2 in- fi'om one end and to specimens'

DV-P5 and P6 midAvay between two of the

studs and I31/2 in. from one end. The set, after

a load of 1,000 lb had been applied to F.^, was

0.068 in. Specimens P5 and P6 failed by

punching through the plywood at the maximum load.

600

500

<5 400

O

s

200*

100^

0

1 ^

0

>-o

D

1 -m —o—lo

1« k>

1

0-

• Of

DV- 1 o 0.2 04 0.6

indenfaf/on in. FiGUKE 18.

Concentrated load on wall DV, load

applied to inside face. Load-indentation (open circles) and load-set (solid circles) results for specimens DV-Pl, PZ, and P2.

800

I

o

600

400

200

0'

1—*

0

/

—0—

1

0u

/

I j'

m

1

1 ®

1®

Ie (

1 /

DV-4 o 0.2 0.4

in dentation

0.6

in. FiGUEE 19.

Concentrated load on loaU DV, load applied to outside face. Load-indentation (open circles) and load-set (solid circles) results for specimens DY-P4, PS, and P6.

[15]
5. Impact Load

The results of the impact-load test are jriven

in table 4 and in figure 20 for specimens

DV-Il, 12^ and IS loaded on the inside face,

and in figure 21 for specimens DV-IJt., 15, and

/6, loaded on the outside face.

deflection in.

i<^iGtrKE 20.

Impact load on wall DV, load applied to inside face. Height of drop-deflection (open circles) and heigbt of dropset (solid circles) results for specimens DV-Il, 12, and 13 on the span 7 ft 6 in. The impact loads were applied to the inside

face of specimens DV-Il, 12, and 13, the sandbag striking the center of the specimen midway

between two studs. The effects are given in

table 5. Table 5.

Effects of impact load on wall specimens DV-Il

,

12, and 13, loaded on inside face

Specimen 11 Specimen IS Specimen IS

. Description of elTecta Height

of drop Deflection

Height

of drop Deflection

Height

of drop Deflection

ft in. /( in. ft in. Face loaded: Crack in plywood 2 5 0.90 3.5 0.96 Face broke where sand- bag struck 5.0 1.08 4.5 1.07 4.5 1.02 Face not loaded: Crack in plywood . . . 6.0 2.25 6.0 2.08

Separation otface from

studs - - 6.0 2.50 6.5 2.23

deflection in,

FiGUEE 21.

Impact load on icall DV, load applied to outside face. Height of drop-deflection (open circles) and height of dropset (solid circles) results for specimens DV-H, 15, and 16 ou the span 7 ft C in.

The impact loads were applied to the outside

of specimens DV-L!f, 15, and 16, the sandbag

striking the center of the specimen midway between two studs. After a -i-ft drop, developed a long crack in the outside (loaded) face

under the bag.

The deflection was 0.93 in. The inside face

separated from the spline and stud on one side

after a 7-ft droj). The deflection was 2.86 in. In 15, the S^/o-ft drop produced a noise that

apparently indicated a glue failure ; the deflec- tion was 1.01 in. In 16, the 6y2-ft drop produced a noise that apjDarently indicated a glue

failure. The deflection was 1.57 in. After the 10-ft drop, the set in specimen 11^ was 0.282 in.; in 15, 0.122 in.; and in 16,

0.121 in.

6. Racking Load

Wall specimen DV-Rl under racking load is shown in figure 22. The results of the rackingload test for specimen DV-Rl, R2, and R3 are given in table 1 and figure 23.

[16]
deforma fion in.jd ft

FiGUKE 23.-Racking load on ivall DV.

Load-deformation (open circles) and load-set (solid circles) results for specimens DV-Rl, Ri, and R3. The loads are

in kips per foot of actual width of specimen.

The racking loads were applied to the top

plate, and the stop was m contact with the bottom plate at the diagonally opposite corner of

the specimen. Under a load of 1.50 kips/ft, the

two 4- by 8-ft plywood sheets on each side of

the specimen Rl exhibited relative vertical dis- placement. Crushing occurred at the front

lower plate, and the top plate failed in compression under the maximum load. A noise,

apparently glue failure, was heard at 0.8 kip/ft in specimen R2. At 2.2 kips/ft crushing oc- curred at the bottom plate and at 2.3 kips/ft

the top plate sheared from the plywood.

Under maximum load, the top plate crushed.

A loud noise, apparently glue failure, and

crushing of the top plate occurred at 0.97

kip/ft in R3. The bottom plate at the stop

began to fail in crushing at 1.27 kips/ft.

V. PARTITION DW . .

1. Sponsor's Statement

Partition DW was like wall 7?F, except that

both faces were like the inside face of the wall

specimens. The i:)artition specimens were as- sembled and fastened together in the same manner as the wall specimens.

The price of this construction in Washington, D. C, as of July 1937 was $0.24/ft2.

{a) Four-Foot Partition Specimens

The 4-ft partition specimens shown in figure

24 were 8 ft 0 in. high, 3 ft 11% in. wide, and

3 in. thick. Each was a wood frame to which

the faces were fastened. The frame consisted

of four studs, fastened to transverse members, 5, at top and bottom. There were two

lines of blocks, extending between the studs. Faces, Z>, each consisted of one piece of plywood. Plates, extended across the top and

bottom ends of the specimens, and half splines,

F^ were inserted between the faces at the sides. Studs.—The studs, A, were Douglas fir, 25/32 by 21/2 in. (nominal 1 by 3 in.) 7 ft 71/2

in. long, spaced 1 ft 3 in. on centers. Transverse menibers.—The transverse members, B, were Douglas fir, '^%2 by 2i/^ in. (nominal 1 by 3 in.) 3 ft 10% in. long, extending across the ends of the studs. The trans- verse members were fastened to the studs by

6d box nails driven through the transverse members into the ends of the studs, two nails

to each stud end.

Blocks.—Blocks, C, were Douglas fir, -y^o

by 21/^ in. (nominal 1 by 3 in.) 1 ft 2i^ in.

[17]
Figure 24.

Four-foot partition specimen Dir.

A, Stud ; D, transverse member ; C, block ; D, face ; E, plate ; F, half spline.

lonsr, inserted between the studs in two lines about equidistant from the transverse members

and each other. The blocks were fastened to the studs by 6d box nails. Two nails were

driven through the outer studs into the ends

of the outer blocks and one nail through each

stud.

Faces.—Faces, Z>, were each one piece of

Douglas fir plywood, moisture-resistant type,

14 in. thick, 8 'ft 0 in. long, and 3 ft 11% in. wide. Each face was fastened by glue to all the frame members, which had been coated

with the glue mixture.

Plates.—Both floor and top plates, E, were Douglas fir, II/2 by 21/2 in. (nominal 2 by 3 in.)

3 ft 11% in. long. The plates were inserted

between the faces of the specimens after the

faces had been attached to the frames, and were

fastened in place by 6d box nails driven

through the faces and spaced approximately 6

in. apart. There were also three 8d common

nails driven through each plate into the trans- verse member, spaced about halfway between

the studs. In some sijecimens, glue had been

partially applied to the sides of the plates, but

in other cases this was omitted. > Half splines.—Half splines, were Douglas

fir, by 21/0 in. (nominal 1 by 3 in.) 7 ft 9 in. long. The half splines were inserted between the faces of the specimens after the

faces had been attached to the frames, and were

fastened in place by 6d box nails driven

through the faces and spaced approximately

6 in. apart. In some specimens, glue had been

partially applied to the sides of the half

splines, but in other cases, this was omitted.

(5) Eight-Foot Partition Specimens

The 8-ft partition specimens, shown in figure

25, were 8 ft 0 in. high, 7 ft IIV2 wide, and

3 in. thick. The specimens consisted of two

4-ft panels like the 4-ft specimens, joined to- gether and held in place by continuous plates,

E. at top and bottom; and full size spline,

between the specimens.

Plates.—Plates, E, were similar to those for

the 4-ft specimens, and were fastened in the .same way but were 7 ft III/2 in. long.

Spline.—Spline, G. was Douglas fir, ly^ by

21/2 in. (nominal 2 by 3 in.) 7 ft 9 in. long.

The spline was inserted between the faces of

the adjoining panels, and the panels were

fastened by 6d box nails driven through the

faces into the spline along the adjacent edges.

The spacing was about 6 in.

(r) Comments

The partitions of a house consist of panels

similar to the 4-ft specimens, joined together

and held in place by continuous plates at top

and bottom, and wood splines as represented

by the construction of the 8-ft specimens.

Openings for doors are provided by specially

constructed panels. The surfaces of this construction are usually finished with paint.

2. CoMPEESsrv^E Load

The results of the compressive-load test for

partition specimens DW-Cl, and C3 are given in table 6 and in figures 26 and 27.

[18]
Figure 2~>.—Eiyht-foot partition specimen 1)W.

A, Stud; tiaiisTorso member; C, block; D, face; E, plate; F, half spline; G, spline.

T.\i3LE 6.Structural properties of partition D\\

[Weight, ba.scd on face area: 2.61 lb/ft']

Compressive load* Transverse load; span,

7 ft 6 in. Concentrated load; disk, (liam 1 in. Impact load; span.

7 ft G in.; sandbag, CO lb Racking load

Specimen Maximum

load Specimen Maximum

load Specimen Maximuml.>ad Specimen Maximum

load Specimen Maximum

load

CI

Kips/ft^ 8.55

8.71 9.47

Tl 233 278

296

PI

lb 521 700

500

11.

ft 6.0

8.0

7.0

Rl

Kips/ft^ 1.80

1.91 1.79 cs T2 P2 12 R2.. C3 T3 PS IS R3

Average 8.91 Average 209 Average 574 Average 7.0 Average 1.83

» Load applied 0.98 in. (1/3 thickness of the panel) from 1 face,

b A kip is 1 ,000 lb. [19]
The shortenings and sets were obtained from

the compressometer readings for a height of

8 ft. Tlie compressometers were attached to the plates through whicli tlie load was applied

;

the gage length was 8 ft. The lateral deflec- tions plotted in figure 27 were deflections

toward the outside face of the panel. The

speed of the movable head of the testing

machine was adjusted to 0.072 in./min.

For specimens Cl^ C2^ and C3, respectively,

the compressive face buckled at a load of 3.00,

4.00, and 3.50 kips/ft. Loud noises indicating

glue failure were heard at a load of 4.00, 6.00,

and 4.50 kips/ft.

The studs began to crush into the top plate

at 4.67, 5.50, and 5.00 kips/ft. The plywood

on the inside face started separating from the

panel at 7.16, 4.45, and 6.67 kips/ft. The out- side face of 03 began separating aixd buckled

at 6.67 kips/ft.

6

^ 5

"^3

4

3

%

0

I

o

•

o-c

•9

^ O c

co-A

'/ o —o

•

•—J

1 . oo/ ( —o—

.

/ C CO / o

./

/

/ c

^-—o

0 .05 JO .15

shortening in.jdff

FiGUEE 26.

Compressive load on partition DW.

lioad-shortening (open circles) and load-set (solid circles) results for specimens DW-Gl, CZ, and CS. The load was

applied 0.08 in. (one-third the thickness of the panel) from one face of the panel. The loads are in kips per

foot of actual width of specimen.

3. Transverse Load

The results under transverse load are given

in table 6 and in figure 28 for specimens DWTl^ and T3. The speed of the movable head

lateral deflection in

Figure 27.Compressive load on partition DW.

Load-lateral deflection (open circles) and load-lateral set

(solid circles) results for specimens DW-Cl, C2 and C3. The load ^Yas applied 0.98 in. (one-third the thickness

of the panel) from one face of the panel. The loads are in kips per foot of actual width of specimen.

.SOD

^00

i

I

100

0

o

o o

o

0 o

a

o-o

00

1 /

it DW

o 0.5 1.0 15

deflecfion in. Figure 28.

Transverse load on partition DW.

Load-deflection (open circles) and load-set (solid circles) results for specimens DW-Tl, T2 and T3, on the span 7

ft 6 in. The load (lb per sq ft) is the total load divided by the product of the span and the width of the specimen.

[20]
of the testing machine was adjusted to 0.172

in./min.

For specimens Tl^ T2, and respectively,

the top plywood started to buckle at a load of

100, 120, and 160 Ib/ft^. Noises were heard,

apparently due to glue failure, at 182, 239, and

259 lb/ft2. At 140 lb/ft2 the upper plywood

of Tl separated from the splines. At 219

Ib/ft^ one spline broke, and at 228 Vojii- the

other spline of Tl failed in tension. The upper

plywood of T2 separated from the half splines

at 262 lb/ft-. Under maximum load the lower

plywood of Tl failed in tension. Examination

after test disclosed that in Tl three inner studs

failed in compression and two outer studs

failed in tension; in T2 three studs failed in

compression; and in T3 two studs failed in

comi)ression.

4. Concentrated Load

The results of the concentrated-load tests are given in table 6 and in figure 29 for specimens

DW-Pl, P2, and P3.

600

500

^ 400

I

§ 200

o

I

ICO*-

0

1—•

1 O-i

1

o-o-

-o-f


1• o—k 1

1»

1• oJ:,

-O-fO

\/ DW

o Q2 OA 0.6

indentation in. FiGUEE 29.

Concentrated load on partition DW.

Load-indention (open circles) and load-set (solid circles) results for specimens DW-Pl, Pi, and P3.

The concentrated load was applied to the

face of specimens DW-Pl, P2, and P3, midway between two studs and 15i/^ in. from one

end. Under this maximum load on each specimen the disk punched through the plywood.

5. Impact Load

The results of the impact-load tests are given

in table 6 and in figure 30 for specimens DWI

0'

o

o <

O

0—

I

o o

OKD

• c

V

0 / 2

FiGI-EE 30.- defleciion in. -Impact load on partition DW.

Height of drop-deflection (open circles) and height of dropset (solid circles) results for specimens DW-Il, 12, and IS on the span 7 ft 6 in. U. 13, and 13. The sandbag struck the center

of the face, midway between two studs. The

effects are given in table 7. Table 7.

Effects of impact load on partition specimens

DW-Il, 12, and 13

Description of efEects

Face loaded: Crack in plywood

Face broke where sand- bag struck Face not loaded: Crack in plywood

Face broke where sand- bag struck

Specimen II

Height

of drop De

flection

1.33

Specimen 12

Height

of drop

4.5

5.0

7.0

7.5

Deflection

l.U

1.14

2.75

Specimen 13

Height

of drop

6.0

Deflection

1.53

[21]
6. Eackixg Load

The results under racking load for specimens

DW-El, B2, and R3 are shown in table 6 and

hgure 31. The racking loads were applied to the top

plate, and the stop was in contact with the

bottom plate at the diagonally opposite corner

of the specimen. Noises, appai'ently glue fail- ure, were heard from specimens Rl and E3,

respectively, and at a load of 0.90 and 1.12 kips/ft. The top plate started crushing in

specimens Rl, R3, and R3 at a load of 1.78,

1.56, and 1.20 kips/ft, respectively. The bottom

plate started crushing at a load of 1.78, 1.75,

and 1.60 kips/ft. Under maximum load, the

top plate of each specimen failed completely.

VI. FLOOR DX

1. Spoi^sor's Statement

Floor DX was designed as a short-span

floor panel and consisted of lightweight wood

joists and solid bridging with plywood as both

faces, the faces being fastened by glue. The

faces were subjected to a pressure of 86 Ib/in.- on the joist, header, and bridging surfaces for a period of 35 minutes while the glue hardened.

deformation in.jdff

Figure 31.Racking load on partition DW.

Load-deformation (open circles) and load-set (solid circles) results for specimens DW-Rl, R2, R3. The loads are in kips per foot of actual width of specimen.

FiGUEE B2.—Floor DX.

A, joist ; B, header ; C, bridging ; D, flooring ; E, ceiling ; F, half splines.

[22]
To hasten the time of set, the temperature of

air surrounding work in the presses was raised

to 141° F by panels of infrared light. Tlie

sj^ecimens were not painted.

The price of this construction in Washington, D. C. as of July 1937 was $0.3S/ft2.

(a) Description of Specimens

The floor specimens DX, shown in figure 32, were 8 ft 0 in. long, 3 ft 11% in. wide, ancl 3%6 in. deep. Each specimen had five joists,

.4, fastened to headers, B. There at ere tAvo

lines of solid bridging, extending between

the joists. Flooring, Z>, and ceiling, each

consisted of one piece of plywood. Half

splines, F, were inserted betAveen the faces at the sides. Joists.—The joists. A, were Douglas fir, -%2 by 21/2 in. (nominal 1 by 3 in.) 7 ft. lOi/^

in, long, spaced lli/g in. and 11% in. ai:)art, as

shoAA-n in figure 32. Headers.—Headers, Z?, were Douglas fir, by 21/2 in. (nominal 1 by 3 in.) 3 ft. 101/4

in. long, extending across the ends of the joists.

Tlie headers were fastened to the joists by Gd

box nails driA'en through the headers into the

ends of the joists, two nails into each joist end.

Bridging.—The solid bridging, C, Avas Douglas fir, -%2 by 21/2 in. (nominal 1 by 3 in.)

10% and 10% in. long, inserted betAveen the

joists in two lines about equidistant from the

headers and each other. The bridging AA^as fastened to the joists by 6d box nails. Two

nails Avere driven through the outer joists into

the ends of the bridging. Fastenings at the

inner joists were made by one nail toenailed

through the joists alternating Avith tAvo nails

driA^en through the joist into the ends of the

bridging.

Flooring.—Tlie flooring, 7), was one piece of

Douglas fir j^lyAvood, moisture-resistant type,

y<2, in. thick, 8 ft 0 in. long, and 3 ft 11% in. Avide. It was fastened by glue to the joists,

headers, and bridging, which had been coatect

Avith the glue mixture. There Avere also three

4d finishing nails driA'en through the flooring

into each header, spaced approximately 1 ft 9 in. apart.

Ceiling.—The ceiling, E, was one piece of

Douglas fir plyAvood, exterior type, %(; in. thick, 8 ft 0 in. long, and 3 ft 11% in. Avide. It Avas fastened by glue to the joists, headers,

and bridging, which had been coated Avith the

glue mixture. There Avere also three Id finish- ing nails driA^en through the ceiling into each

header, spaced approximately 1 ft 9 in. apart.

Half splines.—Half splines, Avere Douglas

fii-, ~%2 by 21/2 in. (nominal 1 by 3 in.) 8 ft

0 in. long. The half splines Avere inserted betAveen the flooring and ceiling after the flooring

and ceiling Avere attached to tlie joists, headers,

and bridging. The half splines were fastened

in place by 6d box nails driven through the

flooring and ceiling and .spaced approximately

6 in. apart.

2. Transverse Load

The results of the transverse load on floor

specimens DX-Tl., T2^ and T3 are given in

table 8 and in figure 33. The transverse loads

Avere applied to the uj^per face. Table 8.

Struct ural properties of floor DX

[Weight., based on face area: 3.31 Ib/ft^]

Transverse load; span, 7 ft 6 in. Concentrated load;

disk, diani 1 in.

Impact load; span,

7 ft 6 in.; sandbag, 60 lb

Siioeimen Maximumload Specimen

Maximum

load Specimen

Maximum

load

Tt

Ih/ff-323 320

320

PI

Ih

si ,000

'>1,000

"1 ,000

11

ft

I'lO.O

I'lO.O

I'lO.O P2 12 TS PS IS

Average.. 321 Average. 1,000 Average )0.0

' Specimen undamaged. Ttst disoontinucil.

i> No vi.silile fuilure. Test discontinued. 400

deflection in. Figure 33.

Transverse loud on floor DX.

liOad-deflection (open circles) and load-set (solid circles) results for specimens DX-Tl, T2, and TS on the span 7

ft 0 in. The load (pounds per square foot) is the total load divided by the product of the span and width of the

specimen.

[23]
The speed of the movable head of the testing

macliine was adjusted to 0.15 in./min.

Loud noises, apparently due to glue failure, were first heard in specimens 27, T^, and T3^

at a load of 277, 255, and 293 Ib/ft^, respectively. Under maximum load, Tl failed in the

glue joint between top face and one end plate;

the bottom face of T2 buckled; and one half

spline broke in tension under a loading roller in T3. Examination after tests showed a tensile failure in one spline, a compressive failure

in the other spline and in two joists, and horizontal shear in one joist of Tl.

The middle joist of T2 failed both in tension

and in horizontal shear. One spline failed in

tension under a loading roller; two joists had

horizontal shear failures; and the plywood had

separated from the joists in T3.

3. Concentrated Load

The results of the concentrated load on speci- mens T)X-P1^ P2^ and P3 ai'e gi^-en in table 8 and in figure 34. The concentrated load was applied to speci- mens DX-Pl., P2, and P3 18i/^ in. from one edge and 18 in. from one end.

After the concenti ated load had been applied

and removed, the set in specimen DX-Pl was

0.034 in. ; in PB, 0.043 in. ; and in P3, 0.050 in. No other effects were observed.

indenfafion in. Figure 34.

Concentrated load on floor DX.

Load-indentation (open circles) and load-set (solid circles) results for specimens DX-Pl, Pg, and P3.

4. Impact Load

The results of the impact-load test on speci- mens DX-IJ, 12, and 13 are shown in table 8

and in figure 35.

deflecfio/1 in. Figure 3o.—Impact load on floor DX.

Height of drop-deflection (open circles) and height of dropset (solid circles) i-esults for specimens DX-11, 12, and 13, on the span 7 ft 6 in.

After a drop of 4.0 ft on Tl, 2.5 ft on 12,

and 3.5 ft on 13, a noise was heard, apparently

due to glue failure. No other effects were

observed. After a drop of 10 ft, the set in II was 0.013 in.; in 12, 0.078 in.; and in 13,

0.075 in.

VII. FLOOR DT

1. Sponsor's Statement

Floor DT was designed as a long-span floor panel and consisted of lightweight wood joists

and solid bridging with plywood as both faces,

the faces being fastened by glue. The faces were subjected to a jDressure of 86 lb/in.- on

the joist, header, and bridging surfaces for a period of 35 minutes while the glue hardened.

To hasten the time of set, the temperature of

air surrounding work in the presses was raised

to 141° F by j^anels of infrared light. The

specimens w-ere not painted.

[24]
The price of this construction in Washington, D. C. as of July 1937 was $U.38/ft-.

{a) Description of Specimens

The floor specimens DY, shown in figure 36, were 12 ft 6 in. long, 3 ft 11% in. wide, and

6%6 in. deep. Each specimen had five joists,

.1, fastened to headers, B. There were five lines of solid bridging, 6', extending between the

joists. Flooring, Z>, and ceiling, each consisted of two pieces of plywood. Joints in the

plywood were butt joints, placed over the centers of lines of bridging. Splice strips,

overlapped the jomt on the flooring, and splice

strips, 6-', the joint in the ceiling. Half splines, were inserted between the faces at the sides. Jouts.—The joists. A, were Douglas fir, 25/32 by 51/2 in. (nominal l by 6 in.) 12 ft 41/2

in. long, spaced lli/g and 11% in. apart, as shown in figure 36. Headers.—Headers, 5, were Douglas fir, ''%2 by 51/0 in. (nominal 1 by 6 in.) 3 ft. IQi^

in. long, extending across the ends of the joists.

The headers were fastened to the joists by 6d

box nails driven through the headers into the

ends of the joists, three nails into each joist

end.

Bridging.—The solid bridging, was

Douglas fir, by 5I/2 in. (nominal 1 by 6

in.) 10% and 10% in. long, inserted between

the joists in five lines, spaced as shown in figure

36. Tlie bridging was fastened to the joists

by 6d box nails. Three nails were driven

through the outer joists into the ends of tho

bridging. Fastenings at the inner joists were made by one nail toenailed thi'ough the joists

alternating with two nails driven through tho

joists into the ends of the bridging.

Flooring.—The flooring. Z>, was two pieces of

Douglas fir plywood, moisture-resistant type,

1/2 in. thick and 3 ft 113/4 in. wide. One piece was 8 ft 0 in. long and the other 4 ft 6 in. long.

They were fastened by glue to the joists,

headers, and bridging, which had been coated

with the glue mixture. Three 4d finishing

nails, spaced approximate!}' 1 ft 9 in. apart, were driven through the flooring into each

header.

CeiUng.—The ceiling, was two pieces of

Douglas fir plj'wood, exterior type, %6 in. thick and 3 ft 11% in. wide. One piece was 8

ft 0 in. long and the other 4 ft 6 in. long.

They were fastened by glue to the joists,

headers, and bridging, which had been coated

with the glue mixture. Three 4d finishing

nails, spaced approximately 1 ft 9 in. apart, were driven through the ceiling into each

header. The joint was over the center of a

line of bridging, and was placed at the oppoFiGfRE Z^.—Floor DT.

A, joist ; B, header ; C, bridging ; D, flooring ; E, ceiling ; F, splice strip ; O, splice strip ; H, half splines.

[25]
site end of the specimen from the joint in the

flooring.

Splice strips.—Splice strips, F and 6^, were

'Douglas fir plywood, moisture-resistant type, % in. thick, 4 in. wide, and 10% and 10% in. long. The strij^s were placed symmetrically

over a line of Bridging, which had been cut back % in. Each splice strip was fastened by

three 3d box nails, driven through the strip

into the bridging. Overlapping edges of floor- ing and ceiling were fastened by glue. Splice

strips, F, joined the flooring pieces and splice

strips, (x, the ceiling.

Half splines.—Half splines, H, were Douglas

fir, -%2 by 51/2 ill- (nominal 1 by 6 in.) 12

ft 6 in. long. The half splines were inserted

between the flooring and ceiling after the floor- ing and ceiling were attached to joists, headers,

and bridging. The half splines were fastened

in place by 6d box nails driven through the

flooring and ceiling and spaced approximately

6 in. apart.

2. Transverse Load

Floor specimen T)Y-T1 during the trans- verse-load test is shown in figure 37. The

results of the transverse-load test on floor speci- mens DY-Tl, T2, and T3 are given in table 9, and in figure 38. Table 9.

Structural properties of floors DY and DYa

[Weight, based on face area: 4.55 lb/ft*]

Transverse Concentrated Impact load;

load; span, load; disk weight of Construc- 12 ft 0 in. diain, 1 in. sandban, 60 lb tion symbol Maxi- MaxiSpeci- Speci- mum Speci men load men load

lb//t^ lb ft [Tl 329 Pl a 1 000 11 • 10.0 DY. |t2 348 P2 > 1 ,000 12 » 10.0 (t3 377 P3 800 13 « 10.0

Average. 351 10.0

[Tl 440 DYa |t2 521 IT3 375

Average 445

' Test discontinued. No failure.

FiGUKE 37.Floor specimen DY-Tl during transverse load test. [261
400

^ 300

"§

JO 200

^ /OO

0

0 <tf o

cJ o

o

—

or 0 0.5 1.0 l.d defiedion In. FiGUKE oS.

Transverse load on floor DY.

Load-deflection (open circles) and load-set (solid circlos) results for specimens DY-Tl, T2, and T-". on t)ie span

12 ft 0 in. The load (pounds per square foot) is the

total load divided by the product of the span and the width of the specimen.

The speed of the movable head of the testing

machine Avas adjusted to U.21 in./min.

Under the maximum load, specimens T'i, T2,

and T3 failed in tension at the transverse butt

splice in the ceiling plywood as sliown in figure

39. Examination after test disclosed a failure

in one half spline, horizontal shear failure in

four joists, and tensile failure in two joists of

Tl. Three joists failed by horizontal shear in

T2. One half spline and one joist broke in

tension, and three joists failed in horizontal

shear in T3.

3. Concentrated Load

The results of the concentrated load on speci- mens DY-Pl, P2, and P3 are given in table 9

and in figure 40. The concentrated load was applied 18 in. from one edge and 18 in. from one end of

specimens DY-Pl., P2, and P3. Under a load

of 800 lb, the plywood cracked in specimen

P3. After a load of 1,000 lb had been applied,

the set in Pi was 0.033 in.; and in Z'^, 0.035

in. No other effects were observed.

4. Impact Load

The I'esults of the impact-load test on speci- mens DY-Il, 12, and 13 are shown in table 9 and in figure 41.

FiGTjEE 39.

Failure in hutt joint of plyivood ceiling of floor specimen DT-Tl.

[27]
=5

700

600

500

400

I 300

I ZOO

100

0

Im /—o

1

1•

CO —o^-o—

-o

0 .05 JO ,15

indentation in. Figure 40.

Concentrated load on floor DY.

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

10

8

4

0

I°~7t

o cJ o

(

O >

-o—h>-

hfO—oco

:> p o

•

Q /°

or 0 0.2 OA 0.6 O.d

deflection in. Figure 41.

Impact load on floor DY.

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

set (solid circles) results for specimens DY-Il, 12, and 13 on the span 12 It 0 in.

Figure 42.

Floor DYa.

A, joist; B, header, 0, bridging; D. flooring; E, ceiling; F, splice strip; H, half splines; I, blocks;

J, scarf joint of ceiling pieces.

[28]
After the 10-ft drop on each specimen, the

set in II was 0.032 in. ; in 0.019 in. ; and in

13^ 0.019 in. No other effects were observed.

VIII. FLOOR DYa

1. Spo]srsoR''s Statement

(a) Description of Specimens

The floor specimens DYa, shown in figure

12, were like floor specimens DY, except that

the ceiling pieces were joined with a scarf joint,

/, slope 1 in 15, instead of a butt joint, and

splice strips, were omitted. The joint between the ceiling pieces Avas made before the

ceiling was applied to the framing members.

The overlapping surfaces were coated with

glue, and subjected to heat and pressure while

the glue hardened. Triangular blocks, /, were

fastened in the four corners of the frame to strengthen the fastenings at these points.

Blocks.—Blocks, /, were Douglas fir, 1% in. by 1% in., beveled face, 51/0 iii- long, fastened

with glue and two 3d box nails to each block.

(h) Coniments

The floors of a house consist of panels,

designed to rest on wood sills or plates, and

are joined together by full size wood splines.

The flooring may be finished with stain and

varnish, or overlaid with hardwood flooring or

other suitable flooring material. The ceiling

is usually finished with paint.

After the transverse-load tests of the DY

specimens had been made, it was pointed out

that if there had been scarf joints in the ceil- ing, the transverse strength would have been

greater. The sponsor furnished the DYa speci- mens having scarf joints to enable the differ- ence in strength to be determined.

2. Transverse Load

The results of the transverse-load test on

floor specimens DYa-Tl, 2'2, and T3 are given

in table 9 and in figure 43. The speed of the movable head of the testing

machine Avas adjusted to 0.21 in./min.

Loud noises, probably caused by the failure

of the glue joints, were first heard at a load

of 360,^240, and 319 lb/ft- for specimens 77,

T2, and T3, respectively. Under the maximum

load, the bottom faces of specimens Tl and

T3 buckled. One spline of specimen Tl failed

in tension and one spline of specimen failed

in horizontal shear. Examination after test

500

400

^ 300

o

o 200

/OO

O

c

o

o

DYa O 1.0 2.0

deflection in. Figure 43.

Transverse load on floor DYa.

Load-deflection (open circles) and load-set (solid circles) results tor specimens DYa-Tl, T2, and T3, on the span

12 ft 0 in. The load (pounds per square foot) is the

total load divided by the product of the span and the width of the specimen.

disclosed separation of top face from the joists

in specimens 27, T2, and To. Three joists

failed in compression and the two joists and

the other sj^line failed in tension in Tl. The

other spline and tAvo joists failed in horizontal

shear; two joists failed in tension; and tAvo

joists failed in comjoression in T2. One spline

and two joists broke in tension; tAvo joists

failed in compression; and one joist failed in

horizontal shear in To. The scarf joints in the ceiling of Tl and

T3 did not fail although the deflection at midspan was 7.9 and 6.0 in. at the time the test Avas stopped after the maximum load had been

reached. AVlien the deflection at midspan AA as

5 in. in T2 and some time after the maximum

load had been reached, the scarf joint failed. There was no failure in the scarf joint for any

of these three specimens at the maximum trans- verse load.

The data of table 9 show that the floor speci- mens subjected to transverse load that had

scarf joints Avere more than 26 percent stronger

than those that had butt joints in the ceiling.

[29]
IX ROOF DZ

1. Sponsor's Statement

Roof DZ consisted of lightweight wood

joists and solid bridging with plywood as both

faces, the faces being fastened by glue. The

faces were subjected to a pressure of 86 lb/in.- on the joists, header, and bridging surfaces for

a period of 35 minutes, while the glue hardened. To hasten the time of set, the temperature of air surrounding A\ ork in the presses was

raised to 1^1° F by panels of infrared light.

The specimens were without rooting material

and were not jiainted.

The price of this construction in Washington, D. C. as of July 1937 was $0.41/ft2.

(a) Description of Specimens

The roof specimens DZ^ shown in figure 44, were lt2 ft 6 in. long, 3 ft 11% in. wide, and

4% ii^- deep. Each specimen had five joists, J., fastened to headers, B. There were five lines

of solid bridging, (7, extending between the

joists. Sheathing, Z>, and ceiling, each consisted of two pieces of plywood. Joints in the

plywood were butt joints, placed over the centers of lines of bridging. Splice strij^s, F,

OA'erlapped the joint in sheathing. Splice

strips, overlapped the joint in the ceiling.

Half splines, 77, were inserted between the

faces at the sides. Joists.—The joists, J., were Douglas fir, -%2 by 31/2 in. (nominal 1 by 4 in.) 12 ft 4y2 in. long, spaced 11% and 11% in. apart

as shoAvn in figure 44. Headers.—Headers, />, were Douglas fir, -•>32 by 31/2 in. (nominal 1 by 4 in.) 3 ft IO14

in. long, extending across the ends of the joists.

The headers were fastened to the joists by 6d

box nails di'iven through the headers into the

ends of the joists, two nails into each joist end.

Bridging. —The solid bridging, C, was

Douglas fir, -%2 by 3I/2 in. (nominal 1 by 4

in.) 10% and 10% in. long, inserted between

the joists in five lines, spaced as shown in figure

44. The bi-idging was fastened to the joists

by 6d box nails. Two nails were driven

through the outer joists into the ends of the

bridging. Fastenings at the inner joists were made by one nail toenailed through the joists

alternating with two nails driven through the

joists into the ends of the bridging.

Sheathing.—The sheathing, Z>, was two

pieces of Douglas fir plywood, moisture-resistant tj'pe, % in. thick and 3 ft 11% in. wide.

One piece was 8 ft 0 in. long and the other

4 ft C in. long. They were fastened by glue

to the joists, headers, and bridging, which had

been coated with the glue mixture. There were

Figure 44.—I2oo/ DZ.

A, joist; B, header; C, bridging; D. sheathing; E, ceiling; F, sheating splice strip; G, ceiling splice

strijj ; II . hali spline.

[30]
also three -id fiuisliiiiji: nails driven throu<j,h the

sheatliing into each lieader, spaced 1 ft "J in. apart. The joint was over the center of a line

of bridging.

Ceiling.—The ceiling, was two pieces of

Douglas fir plywood, moisture-resistant type,

34 ill- tliick and o ft 11% i^^- "^vide. One piece was 8 ft 0 in. long and tlie other 4 ft G in. long. They were fastened by glue to the joists,

headers, and bridging, which had been coated

with the glue mixture. There were also three

4d finishing nails driven through the ceiling

into each header, spaced 1 ft U in. apart. The

joint was over the center of a line of bi'idging

and was ]daced at the op])osite end of the specimen fi-om the joint in the sheathing.

Splire sfi'ip^.—S]>lice strips. E, and G. were Douglas fir ])lywo()d. moisture-resistant type,

% in. thick, -4 in. wide, and 10% in. long. The

strips were placed symmetrically oA'er a line

of bridging, which had been cut back 3^ in. Each splice strip Avas fastened by three 3d box

nails, driven through the block into the bridging. The overlapping edges of sheathing and

ceiling were fastened by glue. Sjolice strips,

F. joined the sheathing pieces and splice strips,

G. the ceiling.

Half f^pliiirs. —Half splines. //. were Doutdas

fir, ~%2 by in. (nominal 1 by 4 in.) 12 ft G in. long. The lialf splines were inserted between the sheatliing and ceiling after the

sheathing and ceiling were attached to the

joists. headei'S, and bridging. The half s]dines were fastened in place by 6d box nails driven

through the sheathing and. ceiling and spaced

G in. apart.

2. Tkansvkksk Load

The results for the transA-erse load on roof

specimens 7>Z-77, and 7\3, are given in

table 10 and in figure 45. Table 10.

li^tructiiral prnpcrtics of roofs DZ and DZa

[Weiabt, based on face area: 3.22 lb/ft-]

Construction symbol

Transverse load; span,

12 ft 0 in. Concentrated load;

disk, diam 1 in.

Si>ecimcn Maximum

load Specimen Maximum

load

DZ

Average

f TlT2

TS

lb '1V 155

173 140

PIpa

PS

lb 800 940

800

1 loG i 847

DZa

TlT2

[ TS

180 227

220 A vcrage . . _ - 209

160

0 Q.5 1.0 1.5 de flee Hon in. FiGUKE 45.

Transverse load on roof DZ.

Lo.ail-dpfleotion (oppu circles) and load-set (solid circles)

i-csuirs lor specimens DZ-Tl, T2, and T.l, on tlie span 12

It 0 in. Tlie load (pouixls per square foot) is the tot.-il load divided by tha product of the sijan and the widtli

of the specimen.

The speed of the movable head of the testing

machine was adjusted to O.o2 iii./min.

I'nder the maximum load, the transverse

joint in the ceiling plywood failed in tension

in specimens 77. T2, and 7'.i, as shoAvn in figure

4G. In 77, one half spline failed at a knot

under the maximum load. After test, examination disclosed horizontal shear failures in all joists of 77. In 7':2, one half spline failed in

tension and in horizontal shear, and three joists

failed in horizontal shear. Three joists of To

failed in horizontal shear.

3. CONCEXTRATED LOAD

The results of the concentrated loads on

specimens DZ-Pl. and PS are shown in

table 10 and in figure 47. The concentrated load was applied to speci- mens DZ-Pl., P2., and PS., 18 in. from one end

and 18 in. from one side. Under the maximum

load, the disk punched through the plywood

of each specimen. No other efi'ects were

obserA'ed.

[31]
FiGUEE 46.

Failure in butt joint of plyioood ceiling of roof specimen DZ-Tl.

900

800

700

•§ 600

-^3 500

I 400

I 800

o 200 <

/00«

I 0<i

1 •

—••

/ —MB

c

/

-•-e—

—

^^7^

-O—^^—Q

/

<2&®

—O

/

1• —o^-o

^—0 1/

V DZ

0 0.1 O.^ 0.3

indentation in. FiGUEE 47.

Concentrated load on roof DZ.

Load-indentation (open circles) and load-set (solid circles) results for specimens DZ-Pl, P2, and P3.

X. EOOF DZa

1. Sponsor's Statement

(a) Description of Specimens

The roof specimens DZa., shown in figure 48, were like roof specimens DZ^ except that the

ceiling pieces were joined with a scarf joint,

1 in 15, instead of a butt joint, and splice

strips, G., were omitted. The joint between the

ceiling pieces was made before the ceiling was

applied to the framing members. The over- lapping surfaces were coated with glue and

subjected to heat and pressure while the glue

hardened.

(5) Comments

For flat-roof construction, the roof panels

are similar to the specimens submitted for test. For pitched-roof construction, the ceiling face

is omitted. In either case, the panels are joined

by continuous plates along the eaves and full- size wood splines between. The sheathing may

be covered by any suitable type of roofing. The

ceiling is usually finished with paint.

After the transverse tests of the DZ speci- mens had been made, it was pointed out that

[32]
*

FiGUKE 48.

Roof DZa.

A, joist ; B, header ; C, bridging ; D, sheatliing ; E, ceiling ; F, slieathing splice strip ; B, half splines.

if there had been scarf joints in the inside face

of the roof, the transverse strength would have

been greater. Tlie sponsor furnished the DZa

specimens having scarf joints to enable the

difference in strength to be determined.

2. Transverse Load

The results of the transverse load on roof

specimens DZa-Tl^ T2, and T3 are given in

table 10 and in figure 49. The speed of the movable head of the testing

machine was adjusted to 0.032 in./min.

Loud noises, probably caused by the failure

of the glue joints, were first heard at a load

of 146, 92, and 169 lb/ft- for specimens Tla,

T2a^ and T3a^ respectively. Upon release of

load of 180 Ib/ft^, the scarf joint failed and

the bottom plywood near the joint buckled in

specimen Tla. The bottom plywood of specimen T2a failed in tension at the third point

at a load of 217 lb/ft-. Under the maximum

load, the scarf joint of specimens T2a and T3a

failed. Examination after test disclosed a tensile failure in four joists of Tla. One joist

failed in horizontal shear and four joists failed

in tension in T2a. Four joists and one half

spline failed in horizontal shear and one joist

and the other half spline broke in tension in

T3a.

The average transverse strength of the roof

specimens Z>Za, having scarf plywood ceiling

I

250

200

150

100

60

0'

• •

»

CO

O—C3 /

1 •

DZa

0 1.0 2.0

defiedion in, Figure 49.

Transverse load on floor DZa.

Load-deflection (open circles) and load-set (solid circles) results for specimens DZa-Tl, T2, and TS, on the span

12 ft 0 In. The load (pounds per square feet) Is the

total load divided by the product of the span and the width of the specimen.

[33]
joints, was 34 percent greater than that of tlie roof specimens Z>Z, wliich liad butt plywood

ceiling joints.

XI. ADDITIONAL COMMENTS BY

SPONSOR

It is estimated that over ten thousand houses

have been built from prefabricated i^anels similar to these specimens as produced by six

different manufacturers. The location of these

houses extends from coast to coast and is usually Avithin a trucking range of 300 miles

from factory.

These constructions are designed to be

erected on any conventional type of masonry

foundation. For pitched roof construction,

ceiling panels are similar to floor panels, except

that if attic space is not to be used for storage,

the flooring face is omitted. Outside walls and

roofs or ceilings are usually provided with

thermal insulation in the form of a fiber blanket having a vapor-proof paper covering

the inside face. A typical section is shown in

fijiure 50.

Figure 50.

Typical details of a house assemhhj having ligMweirjM plywood construction.

PAPvT 2. COMMERCIAL TYPE CONSTRUCTION

I. SPONSOR AND PRODUCT

The specimens were submitted by the Douglas Fir Plywood Association, Tacoma, Wash.,

and were built by the Pease Woodworking Co.,

Cincinnati, Ohio, manufacturers of prefabricated houses employing Douglas fir plywood

in their products. The constructions consisted

of conventional frames with faces of Douglas

fir plywood. The outside face was fastened

by nails, the inside face by nails and glue.

Buildings were designed to be erected on conventional masonry foundations, the wall panels

joined by plywood splines.

II. SPECIMENS AND TESTS

The specimens represented walls, and were

assigned the following symbols : 4-ft and 8-ft specimens with commercial type construction,

EA ; 8-ft specimens with blocking between

studs, EAa\ and 8-ft specimens with diagonal

braces, EAb. The individual specimens were

assigned the designations listed in table 11.

[34]
Tabl!1 1 1

.

Specimen designations

ConElement struc- Specimen Load Load

designs,t ion a^jjlied synibol

Wall EA Cl, C2, C3 Compressive _

.

Upi-)':;'r end Do EA Tl, T2. T3 Transverse liiside face. Do EA I'l, P2. I'S Concentrated _ Do. Do EA I'o. 16 do - Outside' face. Do EA TJ,, To, T6 Transverse Do. Do EA It, 12, 13 Impact"-

.

Inside face. Do EA U, IS. 16 do Outside face. Do EA R1,R2, R3 Racking Near up p e r end. Do EAa Rl.RS.RS do Do. Do EAb R1,R2, hS do Do.

" The concentrated and impact loads were applied to the same

specimen, impact loads first.

Because there was no reason to believe that

the continuous girts, blocks, or diagonal braces

between the studs alfected the compressive,

transverse, concentrated, or impact strength ot the wall specimens, the specimens EAa and

EAh were subjected only to racking load.

The specimens were tested in accordance

with BMS2 with the same exceptions mentioned in Part 1.

III. JMATERIALS

Information on the materials Avas obtained

from the sponsor and by inspection of the

specimens, except that the Forest Products

Laboratory assisted by identifying the species

of wood, and the Eno-ineeriiiff Mechanics Section of the National Bureau of Standards

assisted by determining tlie inoistui-e content

of the wood.

1. Wood

(a) Framing

The wood for the framing was Douglas fir, except in compressive specimen, C2, and racking specimens EA-Rl^ R2^ and R3^ where the

species of wood was hemlock, common No. 1

)!• better, S4S, (surfaced four sides), in the

following sizes

:

"%2 by 21/2 in. (nominal 1 by 3 in.)

1% by 3% in. (nominal 2 by i in.)

(b) PJyicood

Douglas fir, 14 and %6 in., bonded with

vater-resistant protein glue having a soya-bean

and casein base. The Vi-iu- plywood was 3-ply,

wallboard grade, sanded, and comj)lied with

Douglas Fir Plywood Association "Plywall."

The %6"iii' plywood was 3-ply, sheathing

grade, and complied with Douglas Fir Plywood Association 'T*l3'Scord.*" AH Plywood

complied with Commercial Standard CS45-42.

After each specimen was tested, the inside

face was removed to expose the framing, and

samples of framing and j^lywood Avere cut for

identilication of species. Figures 51 to 54 are

typical specimens.

1

Figure 51.Wall EA.

Typical 4-foot specimen.

[35]
Samples of j^lywoocl and framing were taken

from each specimen on the clay the specimen was tested; they were weighed and then dried

to constant weight in an oven at 212° F. The

moisture content, given in table 12, was calculated on the oven-dry weight.

Table 12.Moisture content of the ivood [Determined on the daj' -wall specimen was tested]

Wood

lloisture content Minimum Maximum Average

Framing

Bevel siding

Douglas fir plywood, %-in, Douglas fir plywood, ^ln-in.

Percent

10

8

77

Percent

13

1010

10

Percent

11

9

98

(c) Furring

Furring was wood lath, % by li/o in., in 4-ft

0-in. lengths, true Hr, rough.

{d) Bevel Siding

Bevel siding was hemlock, except for compressive specimen, C2, and racking specimen,

EAa-Rl^ where the species of wood was true

fir, select, grade C or better, 346 by %6 by

71/4 in.

2. Sheathing Paper

Sheathing paper was "Slaters Felt," bituminous-saturated felt-paper base, weight 26 lb/

500 ft^, width 30-in.

3. Nails

All the nails were steel wire nails and are

described in table 13.

Table 13.

Description of nails

Steel Di- Nails Type Size Length wire ameter Finish per gage pound

Penny in. No. in. Box 5 m U 0.080 Bright _ 406 Do 6 2 .0985 -_-do___ 236 Do 8 2% i2y2 .0985 Cement- 186

coated Common _ „ 12 3H 9 . 1483 Bright _ 63

Finishing 3 IH .0073 _-_do___ 807 Lath 3 IH 14 .080 ---do... 568
FiGUKE 54:.—Wall EAb.

Tj-pical S-foot specimen.

[371
4. Staples

Tacker staples, formed of sheet steel, No. 25

IT. S. Standard Gage (0.021i in. thick), 0.05 in. wide; stai:)le Y^q in. wide, %q in. long, coated

with copper film. Tacker staples, formed of sheet steel, No. 26

U. S. Standard Gage (0.0187 in. thick), 0.05 in. wide; staple Vic ii^- "wide, i/o in, long, coated

with copper film.

5. Glue

Casein glue, grade A, ground. Formula:

Casein, G5 percent; lime, 15 j^ercent; and dis- persing agents and undisclosed ingredients,

20 percent. I. P. Laucks, Inc., "Lauxein 888."

6. Paixt

The formula for the interior primer is given

in table 14.

FiGUEE 55.

Four-foot wall specimen EA.

A . Prefabricated outer stud ; B, inner stud ; C, floor plate

;

D, top plate ; E, girt ; F, plywood sheatliing ; (?, sheathing paper ; H, furring ; I, bevel siding ; J, inside face.

Table 14.

Formula for interior priiner

[Pigment 59 percent, vehicle 41 percent, by weight]

Pigment Vehicle

Ingredient Content, by weight Ingredient Content, by weight

Lithoponc Calcium carbonate

Percent90

10 Spar varnish" Bodied oil JMineral spirits

Percent39

457

a- Nonvolatile 50 percent.

IV. WALL FA

t. Sponsor's Statement

Wall EA was a conventional wood frame

with plywood on both faces. The outside face

Avas covered with bevel siding over furring

strips, so that enclosed air spaces were formed,

providing thermal insulation. The outside face was fastened with nails, and the inside face

with nails and glue. The inside face was coated

with a paint primer to provide a vapor barrier.

FiGUEE 56.

Details of outer stud of wall speciinen EA.

A, Stud ; K, dimension lumber

;

L, spline ; M, blocl;.

[38]
The price of this construction in Washington, D. C. as of July 1937 was $0.26/ft^.

(a) Four-Foot Wall Specimens

The 4-ft wall specimens shown in figure 55 were 8 ft 0 in. high, 4 ft 0 in. wide, and 5i^ in. thick. Each was a wood frame to which the

faces were fastened. The frame consisted of

four studs; two prefabricated outer studs, 4,

j and two inner studs, Z/, fastened to a floor

I i^late, and a top i^late, Z>, by nails. There

I Avere two lines of continuous girts, extendj ing between the outer studs along the inside

face, and let into the inner studs. The outside

face consisted of one piece of plywood sheathing, F^ sheathing paper, 6-', furring, //, and

bevel siding, /. The inside face, /, was one

piece of plywood, coated with paint.

Studs.—The outer studs, A, shown in figure

56, were prefabricated members placed at the

sides of the specimens, each consisting of two

pieces of dimension hunber. A', 1% by 3% in. (nominal 2 by 4 in.) 7 ft 7yg in. long, two plywood splines, Z, and three plywood strips, M.

Plywood splines, Z, were each one piece of

Douglas fir plywood, moisture-resistant type,

%6 in. thick, 3 ft 0 in. long, and 5 in. wide,

fastened by glue and nails between the two

pieces of dimension lumber.

Plywood strips, J/, were each one piece of

Douglas fir plywood, moisture-resistant type,

%6 in. thick, 3 in. long, and fi/o in. wide,

fastened by glue and nails between the two

pieces of dimension lumber.

The two pieces of dimension lumber with the

splines and strips betAveen were fastened to- gether by glue and tAveh^e 12d common nails

driA^en through the pieces of dimension lumber,

sj^lines and strips, three nails to each spline and

tATo to each strip.

Each stud AA-as fastened to the floor and top

plates by four 12d common nails driven

through the plates into the stud ends.

Inner studs, Z?, were dimension lumber, 1%

by 3% in. (nominal 2 by 4 in.) 7 ft 7i/g in. long,

spaced 1 ft 4 in. on centers. Each stud was

fastened to the floor and top plates by tAvo 12d

common nails driven through the plates into

the stud ends.

Plates.—The floor plate, C, was dimension

lumber, 1% by 3% in. (nominal 2 by 4 in.) 4 ft 0 in. long.

The top plate, Z>, was two pieces of dimension lumber, 1% by ?>% in. (nominal 2 by 4 in.)

4 ft 0 in. long, fastened by 12d common nails

driven through the plates into the stud ends.

There were two nails clriA^en into the inner

studs. The number of nails in the outer studs

A'aried from two to four.

GirtH.—The two girts, Z, were wood strips,

^%2 by 21/2 in. (nominal 1 by 3 in.) 3 ft 414 in. and 4 ft 0 in. long, spaced 2 ft 8 in. on centers,

fastened to each of the inner studs by two 8d

box nails driven thi'ough the girts into the

studs, and fastened to each of the outer studs

by three 5d box nails toenailed into the studs,

except in the case of specimens FA-Il., 13^ and

76", where the girts extended to the outside

edges of the specimens and Avere let into the

outer studs and fastened to each by tAvo 8d box

nails driven through the girts into the studs.

Sheathing.—The sheathing, was one piece

of Douglas fir plyAvood, moisture-resistant

type, %6 ill- thick, 8 ft 0 in. long, and 4 ft 0 in. Avide, fastened b}^ 8d box nails to the framing

members. The nails Avei'e spaced approximately

41/2 in. apart along the plates, G in. along the

outer studs, and 91/0 in. along the inner studs.

Sheathing paper.—Sheathing paper, 6-', was

laid longitudinally over the sheatliing, and consisted of two sheets 30 in. Avide, lapped 12 in. The pajier Avas fastened by a feAv scattered

tacker staples near the corners of the sheets. Purring.—Furring, //, was strips of Avood

lath, % by 114 in., laid along the plates and

studs, fastened by 3d lath nails, sjjaced 12 in. aj)art.

Bevel siding.—The bevel siding, /, was 15

pieces of Avood siding, 34(5 by %g by 714 in., 4 ft 0 in. long, laid 6% in. to the Aveather,

except in the case of one specimen, Avhere there

Avere three courses Avith vertical joints, the

joints centered over inner studs. Tlie siding was fastened by 8d box nails driA^en through

the overlapping, edges, one nail at each stud,

excejDt at A^ertical joints, Avhere there was a

nail at each side of the joint.

Inside face.—The inside face, Avas one

piece of Douglas fir plyAvood, moisture-resis- tant type, 1^ in. thick, 8 ft 0 in. long, and 4 ft 0 in. wide, fastened by glue and 3cl finishing

nails to the framing members. Tlie glue mixture Avas applied to the outer studs, top plate,

and girts. The nails wei-e spaced 41/0 in. apart

along the plates and girts and 6 in."'along the

studs.

(5) Eight-Foot Wall Specimens

The 8-ft wall specimens, shown in figure 57, were 8 ft 0 in. high, 7 ft 1134 in. Avide, and 514

in. thick. The specimens Avere similar to the

4-ft specimens except for the following : There

were fiA^e inner studs; the plates were 7 ft II34

in. long; the girts 7 ft 4U in. long; the sheathing Avas tAvo pieces 3 ft 11 "'g in. wide with a

vertical joint over the center stud ; the sheathing paper Avas four sheets, lapped 8 in. ; bevel

siding Avas 7 ft 113^ in. long, the inside face

9]
three pieces, the middle piece 4 ft 0 in. wide,

the outer pieces 1 ft 11% hi. wide; vertical

joints were butted joints lapped by splice

strips, N.

Splice strips.—Splice strips, were Douglas

fir plywood, moisture-resistant type, 14 in. thick, 21/4 in. wide, back of vertical joints in

inside face between girts and between girts and

plates. Strips were fastened by glue and

tacker staples. Staples were spaced irregularly,

approximately twenty along each joint.

2. Laboratory Statement

In previously published Building Materials

and Structures Reports on the structural properties of wall construction, the 4-ft and the 8-ft specimens have been of identical construction

except as to specimen width. For these EA

walls, however, the 8-ft specimens do not have

the prefabricated outer studs spaced 4 ft apart

to correspond to the 4-ft specimens. It is, therefore, probable that the compressive and

transverse strengths of walls built in 8-ft or longer widths Avill be smaller than the reported

strengths of the 4-ft wall specimens EA.

3. Compressive Load

The results of compressive load on wall

specimens EA-Cl, C2, and C3^ are shown in

table 15 and figures 58 and 59.

FiGTJitE 57.Eight-foot wall specimen EA.

A, Prefabricated outer stud ; B, inner stud ; C, floor plate ; D, top plate ; E. girt ; F, ply- wood slieathing ; G, sheathing paper ; U, furring ; /, bevel siding ; J, inside face ; N,

splice strip.

[40]
Table 15.

Structural properties of walls EA, EAa, and EAh

[Weight, based on face area: EA, 5.23 lb/ft-; EAa, -1.04 lb/ft =

; EAb, 5.04 lb/ft-]

Construction symbol

Coxiipressivo load-' Ti-ansverse load; span, 7 ft 6 in. Concentrated load;

disk, diarn 1 in.

Impact load; spn,

7 ft 6 in.; sandbag,

60 lb Racking load

SpGciniGii Maximum

load Specimen Maximumload Specimen Maximumload Specimen Maximum

load SpcciniGn Maximum

load

EA

f ci

[ cs

~Kivs/ft^

9 . 50 7.87 9.00

TlT2

T3

w/r300

361 393

PIP2

PS

lb 600

489 470

1112

IS

St^lO.O olO.O dlO.O

RlR2

R3

Kips//l^ 2.54

2.52

2. 14 Average . 8.79 351 520 10.0 e2.40

EA =

[ TA

T5

[ re

294

217

326

PA

P6P6

766

489

595 U

15

Jft

=10.0

"lO.O

<=10.0

Average 279 617 10.0

EAa

1 Rl

\ R2

\ RS

1.78

1.77 1.83

'1.81

EAb

\ Rl

\ R2

[ RS

1.60

1 81 182

n.74

1

• Load applied 1.37 in. (ja the effective thickness of the panel) from the inside face,

t A kip is 1,000 lb.

" Test discontinued. Specimen damaged.

<' Test discontinued. No visible damage.

» Each group of racking specimens, EA, EAa, and EAb, differed greatly from the other groups in the e.'itent and distribution of the glued

surfaces of the inner plywood face.

The compressive Ibaxis were applied 1.37 in. (one-third the effective thickness of the panel)

from the inside face of the panel.

The shortenings and sets shown in figure 58

for a height of 8 ft were obtained from the

compressometer readings. The compressometers were attached to the plates through

which the load was applied. The gage length was 8 ft. The lateral deflections plotted in

figure 59 are deflections toward the outside face

of the wall.

The speed of the movable head of the testing

machine was adjusted to 0.072 in./min.

Under the maximum load, the top plate

crushed locally at the inside edges of the studs.

Under the maximum load, the inside plj'-

wood separated from the studs near the top of

specimen Cl. The inside face buckled. At a

load of 7.0 kips/ft, the inside plywood of 02

buckled and separated from the studs at the

top. Under the maximum load, the top plate

split. The inside plywood of 03 separated

from the top plate at a load of 7.0 kips/ft and

buckled at a load of 8.41 kips/ft. The top

plates crushed at a load of 8.0 kips/ft. Examination after test disclosed a horizontal

shear failure in one stud of 02.

4. Transverse. LoADThe results of the transverse-load test are shown in table 15 and in figure 60 for wall

specimens EA-Tl, T'B, and TS, loaded on the

inside face, and in figure 61 for specimens

EA-TJf., To, and T6, loaded on the outside face. The speed of the movable head of the testing

machine was adjusted to 0.12 in./min.

The transverse loads were applied to the

inside face of specimens EA-Tl, T2, and T3.

For specimens 77, T2, and respectively, the

inside face began to buckle between the loading

rollers at a load of 160, 100, and 200 Ib/ft^, and

loud noises, probably caused by the failure of

the glue joints, were first heard at a load of

95, 140, and 373 \h/it-. At a load of 341 Ib/ft^, one outer stud failed in tension, and the inside

plywood crushed near the tensile failure of the

stud in specimen T2. Under the maximum

load, the inside face of Tl separated from the

top and bottom plates, and one outer stud of

T3 failed both in tension and horizontal shear.

Examination of the specimens after test dis- closed tensile failures in three studs and horizontal shear failures in two studs of Tl. Four

studs broke in tension, two studs failed in compression, and two studs had horizontal shear

[41]
failures in specimen T:l. Two studs failed in

tension, and three studs developed horizontal

shear failures in T3.

The transverse loads were applied to the outside face of specimens EA-Tlf., and T6.

For specimens TJi.^ and T6, respectively,

loud noises, probably caused by the failure of

glue joints, were hrst heard at a load of 128,

180, and 247 Ib/ft^ and the inside face began

to buckle at a load of 233, 200, and 287 lb/ft-.

In specimen Z'.^, one outer stud failed in horizontal shear under a loading roller at a load of

283 lb/ft-. In T6, the inside face broke in

tension at a load of 271 Ib/ft^. Under the maximum load, another outer stud failed in tension

in TIf. Examination after test disclosed three

studs broken in tension and two studs with

horizontal shear failures in specimen T.li.. Three

studs failed in tension and one stud failed by

horizontal shear in T5. Horizontal shear fail- ures were present in four studs, and tensile

failures occurred in two studs of T6.

5. Concentrated Load

Wall specimen EA-PJf. under concentrated

load is shown in figure 1. The results of the concentrated-load test are shown in table 15 and in hgure 62 for wall

specimens EA-Pl, P2^ and P3, loaded on the

inside face, and in figure 63 for wall specimens

EA-PJ^^ Po, and P6, loaded on the outside face. The concentrated load was applied to speci- mens EA-Pl^ P2, and P3 midway between two

of the studs and 1 ft I in. from one end. Each

of the specimens EA-Pl, P2, and P3 failed by

the disk punching through the j^lywood.

The concentrated load was applied to speci- mens EA-PI^, P5, and P6 midway between two

of the studs and 1 ft 4 in. from one end. Speci- mens EA-PI^, P5, and P6, respectively, developed a transverse crack under the loading disk

at a load of 354, 281, and 400 lb. Each of the

specimens failed by the disk punching through

the siding.

10

Q to

O

I 4

to

CO1^

0'

• • 0 —• -©—0

1

>G —•—•—ex

1 -

1 /

1 °

0

-m—• 0 J

1 m •0/0/

1 /

-0

• •o-f—o—

' 7

1/ EA 0 0.1 0.2

ahorfening in. FiGUBE 58.

Compressive load on wall EA.

Load-shortening (open circles) and load-set (solid circles) results for specimens EA-Gl, 02, and GS. The load was

applied 1.37 iu. (one-third of the effective thickness of

the panel) from the Inside face. The loads are in Idps per foot of actual width of specimen.

CD

C!J)

5;

o

10

8

6

4

2

0'

•

0 (

oo

—•

•

1

O G

)

<B

1

—

1 / o-cf—

-ocy e

/ o

•

1 o a7o

1 7

o-

'7

•op

f EA 0 0,1 0.2

lateral deflection in. FiGTJKE 59.

Compressive load on wall EA.

Load-lateral deflection (open circles) and load-lateral .set (solid circles) results for specimens EA-Cl, C2, and 03. The load was applied 1.37 In. (one-third of the effective thickness of the panel) from the inside face. The loads

are in kips per foot of actual width of specimen. Tin- deflections and sets are for a gage length of 7 ft 0 in., the gage lengtli of the deflectometer.

[42]
6. Impact Load

The results of the impact-load test are given

in table 15 and in figure 64 for specimens

EA-ll^ 12, and 13, loaded on the inside face,

and in figure 65 for specimens EA-IJf, 15, and

16, loaded on the outside face. The impact loads were applied to the inside

face of specimens II, and 13, the sandbagstriking the center of the specimen midway

between two studs. After a 21/2-ft drop, the

plywood of the inside (loaded) face of 11

developed a longitudinal crack from the point

of impact of the sandbag to the top of the

panel. A longitudinal split in the inside

(loaded) face over a stud at midspan developed in specimens II and I'B, respectively, at a height-of-drop of 51/2 ft and 6I/2 ft. The deflec- tion was 1.20 and 1.35 in. The sandbag broke

through the inside face of II at a height-ofdrop of 6 ft and broke through the inside face

of m at a height-of-drop of 7 ft. The deflec- tion of II was 1.21 in. and of H, 1.35 in. At a height-of-drop of 71/2 ft, the outside plywood

separated from the studs of II near the point

of impact. The deflection was 2.07 in. After the 10-ft drop, the set in 13 was 0.076

in. The set readings of // and 12 were discontinued after the 6-ft drop because the failure

of the inside face released the plywood from

the studs.

The impact loads were applied to the outride

face of specimens Ih, and IG, the sandbag

striking the siding at the center of the specimen

midway between two studs. After a 6-ft drop,

the siding of under the sandbag developed a crack. The deflection was 1.59 in. The siding

of adjacent to the sandbag broke under a drop of 9 ft. The deflection was 2.05 in. In

specimen 15, the siding above the impact area developed a crack at a 4-ft drop; the siding

struck by the bag broke at a 6-ft drop ; and the

siding below the impact area (toward the

bottom of the wall) failed at a 7-ft drop. The

deflections were, respectively, 1.26 in., 1.53 in., and 1.70 in. In specimen 16, the siding struck

by the bag developed a crack at a 2i/^-ft drop

;

Z50

I

—

/

) —m

0Q«»

/•

/•

( ^0

>y/€-0

-/• a

^ J

' <do 7

1 7

1 7

* w

hr

\J

£4 /

^00

0 0.5 1.0

deflection in. Figure Transverse loud 011 ivall EA, load applied

to inside face.

Load-deflection (open circles) and load-set (solid circles) results for specimens EA-Tl, T2, and T3 on the span 7

ft 6 in. The load (pounds per square foot) is the total load divided by the product of the span and the width

of the specimen.

?3

Vs.

/ —

•

0

0 ••

• c

0 0

1—

o

/ • • o 0/

£f 0 0

—0

-i—0 c/

•900/ ' / 0 m-ocf—o—

r / •OCT 0

'7 maio

W0 1. 0 2.0

de flection in

Figure 61.—Transverse load on wall EA, load applied

to outside face.

Load-deflection (open circles) and load-set (solid circles) results for specimens EA-T!,, T5. and T6 on the span

7 ft 6 in. The load (pounds per square foot) is the total load divided by the product of the span and the width

of the specimen.

[43]
the siding above the bag broke at a 3y2-ft drop;

and after the 10-ft drop, the three pieces of

siding at midheight of the specimen were badly

broken. The deflection after the 2%-ft drop

s

600

400

200

0'

•

1 —m

o

/•

•

o

1

EA-I 0 0,2 0.4 0.6

Figure

indeniafion in. Q2.—ConaeMtrated load on imll applied to inside face. EA, load

Load-indentation (open circles) and load-set (solid circles) results for specimens EA-Pl, P2, and PS.

600

600

^ 400

I

oI 200 to

0'

i o

•

• •

oo o

-T^O O-

/

• •

/

o

O 0 / o

• o—

•

' O/CD/

1/ EA-4 0 0.2 0.4

indenfafion

0.6

in. FiGUKK 63.

Concentrated load on wall EA, loaa applied to the outside face.

lioad-indentation (open circles) and load-set (solid circles) results for specimens EA-Pl,, P5, and P6.

was 0.78 in.; after the 3y2-ft drop, 0.98 in.

;

and after the 10-ft drop, 2.00 in. After the 10-ft drop, the set in 15 was 0.513

in. The set readings of I4. and 16 were discontinued at height-of-drops of 9 ft and 41/2 ft, respectively, because of failure of the siding.

7. Kacking Load

The results of the racking-load test are given

in table 15 and in figure 66 for specimens FARl, R2, and R3.

The racking loads were applied to the top

plate, and the stop was in contact with the

bottom plate at the diagonally opposite corner

of the specimen. The inside plywood broke

from the lower plate near the stop at a load of

1.40 kips/ft for specimen R3 and of 1.60 kips/ft

for specimens Rl and R2. There was a gradual

relative vertical displacement of the edges of

the two pieces of plywood on the outside face

as the load increased. At the maximum load,

the inside plywood was nearly entirely sepa- rated from the framing and the angular dis- placement of the joints iDetween the plates, and

the studs became so great that the joints were

broken niid the specimen failed.

/Of

0 1.0 2.0

deflection in. FiGi'KK 64.

Impact load on wall EA, load applied to inside face.

Heiglit ol" drop-deflection (open circles) and height of dropset (solid circles) results for specimens EA-Il, IS, and IS on tlie span 7 ft 0 in.

[441
10

o

o 4

0'

O

Xi ©

1

o o —0 o—ySo op o

-oM o Joo

1 -•—

1

1

•

1 op-7

1 /

•

1 CD/

V £A-4

1.0 2.0

de flee Hon in. Figure 65.

Impact load on wall EA. load applied to outside face. Height of drop-deflection (open circles) and heiglit of dropset (solid circles) results for specimens EA-JJ,, 15, and 76 on the span 7 ft •> in.

2.5

2,0

to -9^ /.5

C3^

.5:

/.a

0.5

0

<•

/

o

—»• •oo

T /

^— o

•

1 •

r

i]

If

II

1

0 1,0 2.0

de formafion injd fl

FiGXJKE 66.

Racking load on wall EA.

I;oad-deformation (open circles) and load-set (solid circles) results for specimens EA-Rl, R2, and B3. The loads are

in kips per foot of actual width of specimen.

V. WALL EAa

1. Sponsor's Statement

(a) Description of Specimens

The 8-ft wall specimens, shown in figure 67, were 8 ft U in. high, 7 ft 1134 in. wide, and 614

in. thick. The specimens were like the 8-ft wall

specimens, EA,, except for the following: girts,

E, AA^ere omitted; one line of blocks, O, was

extended between the studs at midheight; and

glue was applied only to the blocks and to the

top plate.

Blocks.—Blocks, 0, were dimension lumber,

1% by; 3% in. (nominal 2 by 4 in.) 1 ft 23/g in. long, insei'ted between the studs in a line at midheight of the specimen. The blocks were

fastened to the studs by 12d common nails. Two nails Avere toenailed into the studs alter- nating with two nails driven thx'ough the studs

into the ends of the blocks.

2. Racking Load

The results of the racking-load tests are given in table 15 and in figure 68 for specimens

EAa-Rl, R2, and R3.

The racking loads were applied to the top

plate, and the stop was in contact with the

bottom plate at the diagonally opposite corner

of the specimen. The inside plywood broke

from the lower plate near the stop at a load of

0.80 kips/ft for specimen Rl, and of 1.10 kips/ft for specimens R2 and R3. The final failure was similar to that of the 8-ft speci- mens. EA.

VI. WALL EAh

1. Sponsor's Statement

(a) Description of Spedmens The 8-ft wall specimens, shown in figure 69, were 8 ft 0 in. high, 7 ft II34 in. wide, and 614

in. thick. The specimens were like the 8-ft wall

specimens, EA, except for the following: girts,

E., were omitted ; two diagonal braces, Z', were

let into the studs on half the width of the

specimen ; and glue was applied only to the top

plate. Braces.—Diagonal braces, P, were dimension

lumber, 1% by 3% in. (nominal 2 by 4 in.)

[45]
5 ft 7 in. long, let into the studs and plates at the outside face, and extending from the center of the plates to midheight of one outer stud.

The braces were fastened by 12d common nails,

driven through the braces into the studs and

plates, two nails at each bearing.

(b) Oomments

The outside walls of a liouse consist of panels

similar to the specimens, except that the width

of panels usually corresponds to the side of a

room, and joints are at intersections with partition panels. Wall and partition panels rest on the floor, and are joined together by means

of full-size plywood splines, which extend from

the outer stud of one panel into the open slot in the outer stud of the adjacent panel. The

spline is fastened by nails through the stud.

Sheathing paper, furring, and siding are applied in the field, after the panels are in

place. Openings for doors and windows are provided when fabricating the panels. Frames,

PiGUKE 67.Eight-foot wall specimen EAa.

A, Prefabricated outer stud ; B, inner stud ; C, floor plate ; D, top plate ; P, pl>"wood

sheatliins; G, sheathing paper; H, furring; /, bevel siding; J, inside face; A, spUco

strip ; O, block.

[46]
,Siirih, and doors are applied in the field. Tlie

outside and inside surfaces of this construction

are usually finished with paint.

2. Racking Load

The results of the racking-load tests are given in table 15 and in figure 70 for specimens

EAh-Rl, R2, and R3.

The racking loads were applied to the top

plate, and the stop Avas in contact with the

bottom plate at the diagonally opposite corner of the siDecimen. The inside plywood broke

from the lower plate near the stop at the load

of 1.20 kips/ft for specimen R2, of 1.40 kips/ft

for sj^ecimen Rl, and of 1.60 kips /ft for specimen R3. The final failure was similar to that

of the 8-ft specimens, EA.

\n. ADDITIONAL COIMMENTS BY

SPOXSOE

It is estimated that over five thousand houses

have been assembled from jjrefabricated j^anels

similar to these specimens, as produced by

twelve different manufacturers. The location

of these houses is largely in the middle west. These constructions are designed to be

erected on any conventional type of masonry

2.0

1.5

1.0

0

•

/ m- • —f—

0

Qty o

/ /

m

1• c/o/

f o

) il

7/

m GO 4/-

ij

EAa

0 0.5 1.0 deformation inj6ff

FiGUEE 68.

Racking load on wall specimens EAa.

Load-deformation (open circles) and load-set (solid circles) results for specimens EAa-Bl. lii, and R3. The loads are

in Uips per foot of actual width of specimen.

foundation. Floors are designed to rest on wood sills or plates, and consist of precut joists

and prefabricated floor panels overlaid with

sheathing paper, plywood subflooring, and

finished floor. The floor panels are usually room length (10, 12, 1-1, 16, and 18 ft) by 4 ft 0 in. Avide, and are fastened to the joists by means of nailing strips resting against the

sides of the joists.

Partition panels are similar to wall panels

except that both faces are like the inside face

of the wall panels.

Ceilings consist of precut joists and prefabricated ceiling panels of plywood. The

ceiling panels are usually 8 ft 0 in. wide and

are fastened to the joists by nailing strips.

Eoofs consist of precut rafters, plywood

sheathing, and any suitable t^'pe of roofing.

A typical section, having EA Avails, is shoAvn

in figure 71.

Figure 69.

Eight-foot wall specimen EAb.

P, Diagonal brace.

[47]
CO -9-

\3

<2>

2.0

1.5

1.0

0

—

t c

o o

c

«• (TO

-m


0

*r

EAh

0 1.0 deformation

2.0

in.jdff

FiGUEE 70.

Racking load on toall specimens EAh.

Load-deformation (open circles) and load-set (solid circles) results for specimens EAb-Rl, B2, and R3. The results are in kips per foot of actual width of specimen.

Figure 71.

Typical details of a two-story house

assembly liaring EA tcalls.

The descriptions and drawings were prepared by E. J. Schell and G. W. Shaw, of the

Building Practices and Specifications Section,

under the supervision of V. B. Phelan.

The structural properties were determined

by the Engineering jNIechanics Section, under

the supervision of A. H. Stang, with the

assistance of the following members of the

professional staff : M. Greenspan, Richard W.

Smith, and L. R. Sweetman.

Washington, June 6, 1944.

ir V. S. Govci nmont Pi inring Office : 1945—659430

[48]


BUILDING MATERIALS AND STRUCTURES REPORTS

[Continued from cover page n]

BMS32 Structural Properties of Two Brick-Concrete-Bloclt Wall Constructions and a Concrete- Block Wall Construction Sponsored by the National Concrete Masonry Association 10^ BMS33 Plastic Calking Materials 15^ BMS34 Performance Test of Floor Coverings for Use in Low-Cost Housing : Part 1 10^ BMS35 Stability of Sheathing Papers as Determined by Accelerated Aging 10^ 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 10^ BMS38 Structural Properties of Two "Dunstone" Wall Constructions Sponsored by the W. E. Dunn Manufacturing Co 10^ BMS39 Structural Properties of a Wall Construction of "Pfeifer Units" Sponsored by the Wisconsin Units Co 10^ BMS40 Structural Properties of a Wall Construction of "Knap Concrete Wall Units" Sponsored

by Knap America Ine 10^ 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^ BMS43 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 2 10^ BMS44 Surface Treatment of Steel Prior to Painting 10^ BMS45 Air Infiltration Through Windows 15^ BMS46 Structural Properties of "Scot-Bilt" Prefabricated Sheet-Steel Constructions for Walls,

Floors, and Roofs Sponsored by The Globe-Wernicke Co 10^ BMS47 Structural Properties of Prefabricated Wood-Frame Constructions for Walls, Partitions, and Floors Sponsored by American Houses, Inc 10#

BMS48 Structural Properties of "Precision-Built" Frame Wall and Partition Constructions

Sponsored by the Homasote Co 10^ BMS49 Metallic Roofing for Low-Cost House Construction lO^t BMS50 Stability of Fiber Building Boards as Determined by Accelerated Aging 10^ BMS51 Structural Properties of "Tilecrete Type A" Floor Construction Sponsored by the

Tilecrete Co 10<f BMS52 Effect of Ceiling Insulation Upon Summer Comfort 10^ BMS53 Structural Properties of a Masonry Wall Construction of "Munlock Dry Wall Brick"

Sponsored by the Munlock Engineering Co 10^ BMS54 Effect of Soot on the Rating of an Oil-Fired Heating Boiler 10^ BMS55 Effects of Wetting and Drying on the Permeability of Masonry Walls 10^ BMS56 A Survey of Humidities in Residences 10^ BMS57 Roofing in the United States—Results of a Questionnaire (*)

BMS58 Strength of Soft-Soldered Joints in Copper Tubing 10,^ BMS59 Properties of Adhesives for Floor Coverings 10^ BMS60 Strength, Absorption, and Resistance to Laboratory Freezing and Thawing of Building

Bricks Produced in the United States 1^^ BMS61 Structural Properties of Two Nonreinforced Monolithic Concrete Wall Constructions. . 10^ BMS62 Structural Properties of a Precast Joist Concrete Floor Construction Sponsored by the Portland Cement Association 10^ BMS63 Moisture Condensation in Building Walls 10^ BMS64 Solar Heating of Various Surfaces 10^ BMS65 Methods of Estimating Loads in Plumbing Systems lOi^ BMS66 Plumbing Manual 20^ BMS67 Structural Properties of "Mu-Steel" Prefabricated Sheet-Steel Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by Herman A. Mugler 15(f BMS68 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 3 15^ BMS69 Stability of Fiber Sheathing Boards as Determined by Accelerated Aging 10^ BMS70 Asphalt-Prepared Roll Roofings and Shingles 15^ BMS71 Fire Tests of Wood- and Metal-Framed Partitions 20(J, BMS72 Structural Properties of "Precision-Built, Jr." Prefabricated Wood-Frame Wall Construction Sponsored by the Homasote Co 10(f BMS73 Indentation Characteristics of Floor Coverings 10(f 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 15^ BMS75 Survey of Roofing Materials in the North Central States 15^ BMS76 Effect of Outdoor Exposure on the Water Permeability of Masonry Walls 15(f BMS77 Properties and Performance of Fiber Tile Boards lOi^ BMS78 Structural, Heat-Transfer, and Water-Permeability Properties of Five Earth-Wall

Constructions 20(1 BMS79 Water-Distributing Systems for Buildings 15^

[List continued on cover page iv]

* Out of print.
BUILDING MATERIALS AND STRUCTURES REPORTS

[Continued from cover page iii] BMS80 Performance Test of Floor Coverings for Use in Low-Cost Housing: Part 4 15^ BMS81 Field Inspectors' Check List for Building Construction (cloth cover, 5 by 7% inches) 20^ BMS82 Water Permeability of Walls Built of Masonry Units 20^ BMS83 Strength of Sleeve Joints in Copper Tubing Made With Various Lead-Base Solders. . . 10^ BMS84 Survey of Roofing Materials in the South Central States 15^ BMS85 Dimensional Changes of Floor Coverings with Changes in Relative Humidity and

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

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

and Construction 10^ BMS88 Recommended Building Code Requirements for New Dwelling Construction with Special

Reference to War Housing 20^ BMS89 Structural Properties of "Precision-Built, Jr." (Second Construction) Prefabricated

Wood-Frame Wall Construction Sponsored by the Homasote Co 15^ BMS90 Structural Properties of "PHC" Prefabricated Wood-Frame Constructions for Walls,

Floors, and Roofs Sponsored by the PHC Housing Corporation 15^ BMS91 A Glossary of Housing Terms 15^ BMS92 Fire-Resistance Classifications of Building Constructions 25^ BMS93 Accumulation of Moisture in Walls of Frame Construction During Winter Exposure 10^ BMS94 Water Permeability and Weathering Resistance of Stucco-Faced, Gunite-Faced, and

"Knap Concrete-Unit" Walls 10^ BMS95 Tests of Cement-Water Paints and Other Waterproofings for Unit-Masonry Walls 15^ BMS96 Properties of a Porous Concrete of Cement and Uniform-Sized Gravel 10^ BMS97 Experimental Dry-Wall Construction With Fiber Insulating Board 10^ BMS98 Physical Properties of Terrazzo Aggregates 15<f BMS99 Structural and Heat-Transfer Properties of "Multiple Box-Girder Plywood Panels"

for Walls, Floors, and Roofs 15^ BMS1(X) Relative Slipperiness of Floor and Deck Surfaces 10^ BMSlOl Strength and Resistance to Corrosion of Ties for Cavity Walls 10^ BMS102 Painting Steel 10^ BMS103 Measurements of Heat Losses From Slab Floors 10^ BMS104 Structural Properties of Prefabricated Plywood Lightweight Constructions for Walls,

Partitions, Floors, and Roofs Sponsored by the Douglas Fir Plywood Association 25<}

BMS105 Paint Manual : With Particular Reference to Federal Specifications (5 by 7% inches,

buckram bound) $1.00