Timber Rivets 

in Structural 

Composite Lumber 

Ronald W. Wolfe 

Marshall Begel 

Bruce Craig 

United States

Department of 

Agriculture 

Forest Service 

Forest 

Products 

Laboratory 

General 

Technical 

Report 

FPL−GTR−153 
Abstract 

Timber rivet connections, originally developed for use with 

glulam construction, may be a viable option for use with 

structural composite lumber (SCL) products. Tests were 

conducted on small samples to assess the performance and 

predictability of timber rivet connections in parallel strand 

lumber (PSL) and laminated strand lumber (LSL). The test 

joint configurations were designed to exhibit ìrivet failuresîósome combination of rivet yield and bearing deformation in the compositeóas opposed to wood failure modes, 

such as block-shear tear-out or splitting. 

Results suggest that per-rivet design values should fall between 1 and 2 kN, depending on species and density of the 

composite and load direction with respect to grain of the 

composite strands. Timber rivets performed better in LSL 

than in PSL and better in yellow poplar PSL than in Douglas-fir or Southern Pine PSL; 40-mm rivets in yellow poplar 

LSL gave roughly equivalent performance to 65-mm rivets 

in yellow poplar PSL. 

Comparing rivet yield predictions following the National 

Design Specification recommendations for round nails and 

the much simpler approach of using 2/3 the maximum load 

suggests that the latter approach provides a more consistently reliable evaluation of yield strength for timber rivets. 

Additional study is necessary to assess rivet connection 

performance in SCL when rivet density exceeds 1 rivet/in2

. 

Keywords: connections, timber rivet, SCL, Southern Pine, 

yellow poplar 

October 2004 

____________________________________________________________ 

Wolfe, Ronald W.; Begel, Marshall; Craig, Bruce. 2004. Timber rivets in 

structural composite lumber. Gen. Tech. Rep. FPL-GTR-153. Madison, WI: 

U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 

9 p. 

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Contents 

 Page 

Introduction........................................................................... 1

Objective............................................................................... 1

Scope..................................................................................... 1

Methods ................................................................................ 2

Results................................................................................... 3

Analysis of Results ........................................................... 3

Design Values ....................................................................... 5

Conclusions........................................................................... 7

References............................................................................. 7

Appendix AóTimber rivets in Douglas-fir PSL.................. 8 

Appendix BóTimber rivets in Southern Pine PSL .............. 8 

Appendix CóTimber rivets in yellow poplar PSL............... 9 

Appendix DóTimber rivets in yellow poplar LSL .............. 9 
Timber Rivets in Structural 

Composite Lumber 

Ronald W. Wolfe, Research Engineer 

Marshall Begel, Structural Engineer

Forest Products Laboratory, Madison, Wisconsin 

Bruce Craig, Corporate Technical Director 

Trus Joist, A Weyerhaeuser Business, Annacis Island, BC, Canada 

Introduction 

Timber rivets were originally developed for use in glulam 

and solid-sawn timber. Recent developments in the area of 

engineered composites, however, have produced a number 

of alternative structural products that can be used in similar 

structural applications. In order to use timber rivets in these 

materials, tests must be conducted to characterize strength, 

ductility, and effects of moisture, temperature, and load 

cycling. 

Objective 

The objective of this study is to provide information on rivet 

shear load capacity in structural composites parallel strand 

lumber (PSL) and laminated strand lumber (LSL). The focus 

was on characterizing an average per rivet load capacity 

under conditions where the failure mode was limited to 

bearing deformation in the wood-based composite combined 

with bending in the nail. Variables considered in this study, 

include species, composite type, rivet orientations and load 

direction. 

Scope 

This was a pilot study to obtain timber-rivet connection 

shear capacity for two types of structural composite lumber 

(SCL) products: PSL and LSL. Parallel strand lumber is a 

composite consisting of parallel strips of veneer. These strips 

often exceed a meter in length and are roughly 3 mm thick 

with widths that range from 15 to 20 mm. Laminated strand 

lumber consists of much thinner and shorter elements 

(<120 mm). Although LSL elements are layered (that is, 

with width dimension in parallel planes), they are not all 

oriented with grain parallel to the machine direction of the 

composite product. In all cases, the surface parallel to the 

strand width dimension is referred to in this paper as the 

wide strand face. 

Material used to fabricate test samples was collected to 

represent mill production. Samples of SCL 0.91 m long were 

collected at different times from four different fabricating 

plants over a 1- to 3-week period. The test sample included 

20 to 30 pieces of each product. These included the following three species of PSL and one species of LSL: 

PSLó2.0E Douglas-fir (DF)óVancouver Plant, 

British Columbia 

2.0E Southern Pine (SP)óColbert Plant, Georgia 

2.0E yellow poplar (YP)óBuckhannon Plant, 

West Virginia 

LSLó1.7E yellow poplar (YP)óEast Kentucky Plant, 

Hazard, Kentucky 

Tests were confined to the determination of shear capacity 

when load is applied either parallel or perpendicular to the 

grain of the SCL product. For the PSL products, tests were 

conducted for nails applied both perpendicular and parallel 

to the wide strand face (WSF) (Fig. 1). For the LSL product, 

nails were tested only in an orientation perpendicular to the 

wide strand face. 

Figure 1óStructural composite lumber section. 
2 

Methods 

Individual timber rivets were tested in bending following the 

ASTM F 1575 standard for determination of nail bending 

yield. Sixty rivet tests, including both 40- and 65-mm rivets, 

provided a basis for verifying published yield strengths 

The rivet connection test configuration was two steel plates 

fastened on opposite faces of the SCL sample using four 

rivets per plate. The PSL connections were made using 

65-mm- (2-1/2-in.-) long rivets, and the LSL connections 

used 40-mm (1-1/2-in.) rivets. In all cases, the plates were 

6-mm- (1/4-in.-) thick cold roll steel plate. 

Timber rivets (Fig. 2) are different from conventional nails 

in that they have a round corner rectangular cross section 

rather than a round one. The width-to-thickness ratio of 

these rivets is roughly 2:1. They are normally driven through 

round holes in steel side plates so that the width dimension is 

oriented parallel to the fiber direction in the wood or SCL 

product. Holes in the steel side plates range from 6.7 to 

7 mm in diameter. When the rivet head is driven into the 

hole, the combination of a Rockwell hardness ranging from 

32 to 39 and a wedge shape deforms the steel and anchors 

the head end in the steel plate. The rivet head (8.7 mm wide) 

is rarely driven flush to the surface of the steel plate. 

The SCL samples were representative of mill production. 

Samples of various cross sections and lengths of 0.91 m 

were obtained from three Trus Joist plants. The crosssectional dimensions (e and S in Fig. 1) were kept as supplied by the manufacturer. These were rectangular in shape, 

with the smaller dimension ranging from 133 to 140 mm and 

the larger dimension ranging from 178 to 184 mm. PSL 

samples were selected so that the dimension that would be 

parallel to the rivet axis was the longer dimension (S or e

Fig. 1). For the LSL tests, the rivets (40 mm long) were 

always oriented parallel to the S dimension (Fig. 1), which 

for these specimens was 89 mm. The e dimension for these 

specimens was 133 mm. The SCL samples were cut to 

lengths of 150 mm for samples loaded parallel to the grain 

and 200 mm for those loaded perpendicular to the grain. 

Four basic rivetñplate orientations are shown in Figure 3. In 

each case, the load was applied parallel to the long dimension of the steel plate, shown as a white rectangle with four 

holes. Timber rivets are always inserted with their wide 

dimension parallel to the grain of the wood. For the SCL 

connections, they are oriented either parallel (A) or perpendicular (E) to the wide strand face. This is the first digit in 

Figure 2óTimber (glulam ) rivet. 

Figure 3óSCL test sample configurations. 
3

the orientation code shown in Figure 3. Load direction with 

respect to wood fiber length is denoted by the second letter 

in the orientation code as being either parallel (A) or perpendicular (E) to the wood fiber. 

Of 136 samples prepared to be tested, 11 were rejected due 

to presence of split or uneven plates. A summary of the 125 

rivet tests conducted is provided in Table 1. 

All test joints were fabricated in the dry condition and stored 

in a conditioning room maintained at 21°C, 65% RH until 

the time of testing. 

Steel plates, 76 mm wide by 100 or 127 mm long were 

machined to have four holes drilled on a 2- by 25-mm matrix. Each hole was centered 25 mm from a long edge, and 

two of the holes were 25 mm from one end. The plates were 

fastened on opposing faces of each sample, with one end 

protruding 19 mm above the edge of the test sample. These 

were tested by applying a downward force on the plates, 

imparting shear force and bending moment on the rivets and 

bearing stress in the wood. 

Results 

The maximum loads for each of the tests conducted are 

listed in Appendixes A to D. 

Joint strength was sensitive to load orientation, exhibiting 

higher capacity when load was applied normal to the 6-mm 

dimension of the rivet (AE and EE). This also corresponds to 

a load normal to the length dimension of the wood fibers. 

When loaded in this direction, the rivets compressed and 

densified the wood under the wide face and were bent at two 

locations. The deformed rivet exhibited the characteristic 

ìSî shape of a mode IV failure (Fig. 4). When load was 

applied parallel to the wide dimension of the rivet and parallel to the grain (AA and EA), the rounded narrow face of the 

rivet had a tendency to cleave the wood fiber. In this case, 

the rivets in the PSL bent at only one location (mode III) 

corresponding to the interface between the wood and the 

steel plate. For the denser LSL, where the rivets were only 

40 mm long, the rivets did not bend but remained rigid in the 

side plates and deformed the wood fiber. This corresponds 

more to a mode ìImî type failure (ANSI/AF&PA 2001, 

CWC 2001). 

The PSL exhibited greater splitting than did the LSL when 

loaded perpendicular to the grain. Splits generally followed 

strand contours. They were not always along the glue line, 

but rather ran between gaps where strand ends met. The 

bearing stresses pushed strands apart and outward from the 

surface. Surface fractures ran perpendicular to the load 

direction well beyond the boundaries of the rivet pattern. 

The LSL exhibited fewer lateral splits; failures appeared to 

be confined to bearing deformation. 

Analysis of Results 

Tests of the timber rivets showed a steel yield strength of 

0.96 GPa (average of 60 tests). The values were calculated 

as the bending yield moment divided by section moduli of 

30 mm3

 and 15 mm3 for strong- and weak-axis loading, 

respectively. 

Table 1óSummary of connection tests showing SCL 

product and species and orientation of rivet with 

respect to the wide strand face and load with respect 

to fiber orientation 

Orientationa

Product/Species Rivet Load Reps 

PSLó Douglas-fir E A 10 

 E 11 

 A A 7 

 E 6 

 

PSLóSouthern Pine E A 8 

 E 10 

 A A 6 

 E 6 

 

PSLóyellow poplar E A 10 

 E 10 

 A A 6 

 E 5 

 

LSLóyellow poplar E A 15 

 E 15 

 Total 125 

a

A, parallel; E, perpendicular. 

Figure 4óMode IV (left) and mode III nail failures. 
4 

The average yield and maximum load values of the test 

connections are summarized in Table 2. The yield values 

were derived as the point of intersection of the measured 

loadñdisplacement (Pñδ) curve and a straight line whose 

abscissa intercept is offset from that of the Pñδ curve by a 

distance equal to 5% of the nail diameter and whose slope is 

derived as a straight line fit to the loadñdisplacement data 

between 20% and 40% of the maximum load achieved. The 

offset used was 0.32 mm for the AA and EA configurations 

and 0.16 mm for the EA and EE configurations. The intersection point of these lines is expected to occur at roughly 

two-thirds the maximum load. The average ratio of 

yield-to-maximum load values shown in Table 2 is 0.69. 

Figure 5 shows relative values of yield and maximum load 

for each test configuration of timber rivets in SCL. In all 

cases, rivets loaded about the weak axis (normal to the wide 

face) had the higher maximum load capacity. It is interesting 

to note that rivets in yellow poplar PSL had an apparent 

higher capacity than those in Douglas-fir and Southern Pine 

PSL. At the 90% confidence level, the strength of 40-mm 

rivets in yellow poplar LSL fell above the 90% confidence 

bound on mean strengths for all the rivet connections in 

Douglas-fir PSL, for the Southern Pine AA and EA connections, and for yellow poplar PSL AA and EA connections. 

This difference might be due to the superior tensionperpendicular-to-the-grain strength of yellow poplar. Yellow 

poplar tension-perpendicular-to-the-grain strength listed in 

the USDA Wood Handbook (Forest Products Laboratory 

1999) is 15% greater than that of Southern Pine and 54% 

greater than that of Douglas-fir. A possible explanation for 

this may lie in the prevalence of reaction wood in yellow 

poplar. Reaction wood fibers generally have a thicker ìgelatinousî S2 layer with a larger fibril angle than normal 

wood. When stressed perpendicular to its axis, such a fiber 

may have a greater tendency to deform and stretch rather 

than bend, transfer axial stress, and tear away from adjacent 

fibers. The result is energy dissipation through local deformation rather than bond failure. 

Table 2óYield and maximum load for timber rivets 

in SCL 

SCL 

Yield 

(kN) 

COV 

(%) 

Max load 

(kN) 

COV 

(%) 

DF-PSL-AA 22.2 5 32.0 6 

DF-PSL-AE 27.5 8 43.3 6 

DF-PSL-EA 24.8 7 37.2 6 

DF-PSL-EE 28.9 18 44.6 5 

SP-PSL-AA 19.9 12 27.8 7 

SP-PSL-AE 30.0 24 44.2 8 

SP-PSL-EA 28.1 7 37.6 7 

SP-PSL-EE 31.4 14 46.2 5 

YP-PSL-AA 26.9 19 42.1 12 

YP-PSL-AE 37.3 12 49.3 7 

YP-PSL-EA 27.9 12 41.9 6 

YP-PSL-EE 35.5 11 48.4 5 

YP-LSL-EA 27.4 12 41.5 9 

YP-LSL-EE 34.6 31 49.0 9 

Figure 5óYield and 90% confidence bounds on mean strength of timber rivets in 

three species of PSL and yellow poplar LSL. 
5

It should be noted that a shorter rivet (40 mm) was used with 

the higher density yellow poplar LSL than was used with the 

PSL samples. These shorter rivets had less tendency to bend 

and rotate in the composite, and the failures were closer to 

that of a mode I. 

The load capacity varied with species and joint configuration. For Southern Pine and Douglas-fir, the weakest connections were those having the rivet oriented parallel to the 

WSF with the load applied parallel to the rivet width (AA); 

the strongest connections were those having rivets perpendicular to the WSF with load perpendicular to the rivet width 

(EE). Yellow poplar PSL exhibited little effect of rivet orientation relative to the wide strand face. Per-rivet average 

values in PSL ranged from 3.5 to 5.7 kN for Southern Pine 

PSL, 4.0 to 5.6 kN for Douglas-fir, and 5.3 to 6.2 kN for 

yellow poplar. The yellow poplar LSL with 40-mm rivets 

actually had higher rivet maximum loads than did PSL with 

65-mm rivets. They averaged 5.2 kN when loaded parallel 

to the rivet width and 6.1 kN when loaded perpendicular to 

the rivet. 

Design Values 

The guideline for derivation of design values for round nails 

(National Design Specification for Wood Construction, or 

NDS) uses as its basis an estimate of the connection yield 

capacity. The theoretical derivation of the NDS equations is 

discussed by Aune and PattonñMallory (1986). The NDS 

estimate of design load for nails and spikes varies depending 

on the expected failure mode and the properties of the materials being fastened together. In general, the equations given 

in the NDS predict a yield strength adjusted by a calibration 

factor (KD), which gives a design value roughly equivalent to 

the historic reference of 1/3 the maximum load capacity or a 

displacement of 0.015 in. 

The NDS provides equations for estimating design values for 

round nails. The following Equations (1) to (3) are derived 

from the NDS equations, with modifications made to estimate yield strength for timber rivets in composite materials. 

First, the calibration factor was removed to give an estimate 

of yield strength rather than a design value. Second, the 

diameter (D) was modified (Eqs. (1), (2)) to reflect different 

bearing and bending moment resistances related to the rivet 

shape. For the calculation of the contribution of rivet bearing 

force, we used effective diameters equal to the width 

(DBw = 6.4 mm) and thickness (DBt = 3.2 mm), depending 

on whether load is applied normal to or parallel to the rivet 

width dimension. For calculation of the contribution of rivet 

bending strength, the values used were those that provide an 

equivalent round section modulus. The value for bending 

about the width axis is DSw = 4 mm and for bending about 

the thickness axis is DSt = 5mm. Finally, due to the different 

failure mechanisms for parallel (cleavage of fibers) and 

perpendicular (bearing and densification) to the fiber length 

of the composite, we introduced the factor γ as an adjustment 

on dowel bearing. This was necessary in order to get predictions that agreed with the failure modes observed. 

Mode Im failure Z = DBi pγFem (1) 

Mode IIIm failure Z = (1 2 ) e

1 em

R

k DBi pγF

+

 (2) 

Mode IV failure 

3(1 )

2

e

3 2

em yb

R

F F DS DBγ Z i

+ = (3) 

where 

2

em

3

yb e

1 e 3

2 (1 2 )( / ) 1 2(1 )

γF p

F R DS DB

k R

+ i i = − + + + 

Re is Fem /Fes, 

P penetration of the rivet into the main member = 

L (65 or 40 mm) ñ 0.7 mm (head) ñ 4.8 mm (point), 

γ dowel bearing adjustment (0.7 for parallel to fiber 

and 1 for perpendicular), 

Fem dowel bearing strength of main member (holding 

point), derived following the dowel bearingñspecific 

gravity (SG) relationship inherent in the NDS table 

for Fe values [16612(SG1.84)(6.894 KPa/lb/in2

)], 

where the equivalent SG is 0.5 (ASTM 2001),

Fes dowel bearing strength of side member (310 MPa for 

ASTM A653 steel plate), 

Fyb bending yield strength of the rivet = 

0.97 GPa = 140,000 lb/in2

, 

DB equivalent nail diameter for bearing, and 

DS equivalent nail diameter for bending. 

To get good agreement between the predicted and observed 

failure modes, a γ value (Eqs. (1) to (3)) of 0.7 was used to 

adjust the Fem value for parallel-to-the-grain loading. This 

worked well for the PSL, providing good agreement to the 

observation that all connections loaded parallel to the width 

dimension of the rivet exhibited mode III and all those 

loaded perpendicular to the wide face exhibited mode IV 

failures. 

Yield strength is not nearly as easily identified as maximum 

strength, but it is generally perceived to be more meaningful 

as a basis for setting a design limit state. If the ratios of 

maximum load to yield do not vary widely between different
6 

types of nailed connections, however, basing the design on 

maximum load would eliminate variability due to data interpretation. Historically, the design value of connections was 

set in the range of 1/3 the maximum load capacity or the 

load that gives a limit state displacement in the range of 0.38 

mm. The NDS calibration factors ranging from 2.2 to 3.0 

suggest that 1/3 of ultimate is roughly equal to 1/2 of yield 

or that the maximum load should be 1.5 times the yield 

value. 

Table 3 compares theoretical and empirical yield values and 

the ratios of connection ultimate load capacity to these yield 

values. Assuming that rivet orientation with respect to the 

WSF did not have a significant effect on joint capacity, 

connection strengths were evaluated as a weighted average 

for all specimens tested with the same load-to-rivet orientation in each SCL material. Dividing the ultimate load by the 

predicted yield value gave ratios ranging from 2.0 to 2.3 for 

all values except the yellow poplar SCLs with load applied 

in the A orientation. The yellow poplar PSL appeared to 

have higher bearing values than did the other species. The 

yellow poplar LSL exhibited roughly the same yield and 

strength values as did the PSL despite a smaller penetration 

(40 mm rivet compared with 65 mm rivet). In the case of 

load parallel to the width dimension of the rivet (AE), the 

failure mode (mode I) was bearing deformation in the LSL 

with no rotation or bending of the rivet. 

The last row of Table 3 shows the ratios of measured ultimate strength to measured yield. These values average 1.46, 

ranging from 1.3 to 1.6 in PSL materials and the yellow 

poplar LSL loaded parallel to the grain. In this case, yellow 

poplar ratios for load parallel were 1.55 for PSL and 1.54 for 

LSL. These results suggest that yield strength could be 

characterized as 2/3 the ultimate strength. The apparent 

consistency suggests it would be appropriate to use the 

ultimate strength as a basis for deriving a design value. For 

the yellow poplar LSL loaded perpendicular to the strands, 

the yield value is slightly less than half the strength. To gain 

agreement between the theoretical and empirically derived 

yield values, it may be necessary to provide some adjustment 

to the yellow poplar properties, such as an increase in the 

equivalent specific gravity (SG). 

A higher equivalent SG for the yellow poplar SCLs would 

increase their predicted yield value and reduce their ratio of 

ultimate to predicted yield strength. If the SG value used was 

closer to the measured values, the average ratio of measured 

ultimate strength to predicted yield would be reduced by 

27%, but it would change the predicted failure mode to a 

mode III. For these connections, there was no apparent rivet 

bending. 

Although NDS currently supports the European yield model 

(EYM) for nails, it does not seem practical at this time to use 

it for timber rivets in SCL. First, there is no consistent 

method of determining yield strength for the wide variety of 

engineered wood composites. We need better data on bearing values and their variations within orthotropic composites. Second, the maximum load capacity will be interpreted 

Table 3óConnection strength-to-yield ratiosa

Southern Pine PSL Douglas-fir PSL Yellow poplar PSL Yellow poplar LSL 

3.2 mm 

(load A) 

6.4 mm 

(load E) 

3.2 mm 

(load A) 

6.4 mm 

(load E) 

3.2 mm 

(load A) 

6.4 mm 

(load E) 

3.2 mm 

(load A) 

6.4 mm 

(load E) 

Predicted yield 

Z-III (kN) 15 44 15 41 15 39 13 22 

Z-IV (kN) 18 22 16 22 16 22 18 22 

Weighted average 

8-rivet strength 

33 45 34 44 42 49 41 49 

Strength:predicted yield 2.19 2.04 2.26 1.99 2.75 2.20 3.12 2.21 

Measured yield (kN) 

Rivet A 20 28 22 27 27 37 

Rivet E 28 31 25 28 27 35 27 23 

Measured strength 

Rivet A 28 44 32 43 42 49 

Rivet E 38 46 37 45 42 48 41 49 

Strength:measured yield 1.37 1.52 1.47 1.58 1.55 1.36 1.54 2.09 

a

Observed strength equaled or exceeded 2 times the predicted yield. Observed strength-to-yield ratios averaged 1.55, ranging from 

1.33 to 1.67 across all PSL sample 
7

the same by everyone looking at a given set of data, whereas 

yield may have a range of interpretations. It makes more 

sense to focus on consistency and use a factored adjustment 

applied to the average per-rivet maximum or some lower 

exclusion strength rather than some subjectively derived 

yield point on a nonlinear curve. 

A design value per rivet derived using the ultimate load 

capacity values in Table 3 divided by 3.3 would fall in the 

range of 1 to 2 kN. Using the NDS predicted yield values 

divided by 2.2 give design values in the range 0.85 to 

1.25 kN. These results suggest that the EYM model gives 

conservative estimates of the per-rivet load capacity when 

bearing values are based on equivalent SG. 

Conclusions 

Timber rivet connections are a viable option for engineered 

use of SCL. The 8-rivet connection tests evaluated in this 

study suggest that per-rivet design values should fall in the 

range 1 to 2 kN, depending on the species and density of the 

composite and the load direction with respect to the grain of 

the composite strands. 

Timber rivets performed better in LSL than in PSL. In yellow poplar PSL, the 65-mm rivets had per-rivet lateral shear 

strengths ranging from 5.2 to 6.2 kN, compared with a range 

of 5.2 to 6.1 kN for 40-mm rivets in yellow poplar LSL. 

The higher tension-perpendicular-to-the-grain strength of 

yellow poplar appeared to contribute to significantly higher 

rivet strengths. This, in combination with higher density, 

appeared to give the LSL an advantage over PSL. 

Per-rivet design value predictions based on the NDS yield 

equations for nails require a more refined derivation of rivet 

bearing stress than is obtained using the NDS estimate as a 

function of specific gravity. The greater tendency for splitting when loaded parallel to the fiber direction with the 

narrower dimension of the rivet suggests that shear or cleavage stresses have a greater influence than does bearing. 

Ultimate load capacity provides a better basis for the derivation of design values than the more subjectively derived 

yield strength. 

This study focused only on an evaluation of per-rivet 

strength, with all failures attributed to either rivet bending or 

wood bearing deformation. If the rivet density is increased, it 

is expected that failures may be attributed to block shear tear 

out, which is a function of the tension and shear properties 

of the SCL. 

References 

ANSI/AF&PA. 2001. National design specification for 

wood construction. Washington DC: American National 

Standards Institute/American Forest & and Paper 

Association. 

ASTM. 2001. Standard specification for evaluation of structural composite lumber. ASTM D5456ñ01. West Conshohocken, PA: American Society for Testing and Materials. 

Aune, P.; PattonñMallory, M. 1986. Lateral load-bearing 

capacity of nailed joints based on the yield theory: theoretical development, Res. Pap. FPLñRPñ469. Madison, WI: 

U.S. Department of Agriculture, Forest Service, Forest 

Products Laboratory. 20 p. 

CWC. 2001, Wood design manual. Ottawa, ON: Canadian 

Wood Council. 

Forest Products Laboratory. 1999. Wood Handbookó 

Wood as an engineering material, Gen. Tech. Rep. 

FPLñGTRñ113. Madison, WI: U.S. Department of Agriculture, Forest Service, Forest Products Laboratory. 463 p. 
8 

Appendix AóTimber rivets in Douglas-fir PSL 

No.

test

Ident.

no.

Nails/load

orientation

Yield load 

(×103

lb/in2

) 

Max. load

(×103

lb/in2

)

Slope

(×103

lb/in2

/in)

1 82a AA 4.88 6.99 95.62

2 82b AA 5.12 7.45 85.69

3 84a AA 5.14 8.00 147.88

4 84b AA 5.01 7.13 61.85

5 86a AA 4.44 6.46 55.33

6 86b AA 5.18 7.13 106.91

7 94d AA 5.17 7.16 83.79

1 82c AE (a) 8.63 29.05

2 84c AE 5.85 9.75 41.97

3 84d AE 6.28 9.84 36.25

4 86c AE 6.68 10.48 40.82

5 86d AE 5.47 9.66 45.14

6 94c AE 6.60 10.00 34.28

1 78a EA 5.40 8.07 74.82

2 79a EA 4.97 7.43 90.49

3 79b EA 5.40 7.68 112.09

4 87a EA 5.52 8.00 53.66

5 88b EA 5.83 8.85 67.59

6 90a EA 6.18 8.83 89.70

7 92a EA 5.71 8.44 64.89

8 92b EA 5.59 8.54 96.44

9 94a EA 6.02 8.82 90.16

10 94b EA 5.24 8.87 92.34

1 78d EE 6.50 10.37 56.46

2 79c EE 6.42 9.63 56.46

3 79d EE 5.09 9.75 27.45

4 80c EE 5.64 9.82 37.80

5 80d EE 6.29 10.20 36.57

6 82d EE 7.70 10.58 47.07

7 88c EE 8.51 10.76 38.64

8 88d EE 5.72 9.62 39.97

9 90c EE 4.34 10.02 31.36

10 92c EE 7.60 10.38 38.37

11 92d EE 6.33 9.17 43.95

a

Pñδ curve deflection error. 

Appendix BóTimber rivets in Southern Pine PSL 

No.

test

Ident.

no.

Nails/load

orientation

Yield load 

(×103

lb/in2

) 

Max. load

(×103

lb/in2

)

Slope

(×103

lb/in2

/in)

1 25a AA 3.99 6.18 70.82

2 25b AA 3.77 5.54 54.92

3 27a AA 4.56 6.14 94.68

4 27b AA 5.04 6.80 81.36

5 29a AA 5.08 6.71 83.67

6 29b AA 4.46 6.15 79.34

1 25c AE 6.10 9.70 33.00

2 25d AE 5.11 8.94 36.10

3 27c AE 6.17 10.19 36.16

4 27d AE 7.01 10.72 45.00

5 29c AE (a) 9.22 47.36

6 29d AE 9.32 10.79 29.18

1 13a EA 5.96 8.07 73.59

2 13b EA 6.59 8.71 109.77

3 18a EA 6.49 8.09 73.06

4 18b EA 5.64 7.72 106.43

5 20a EA 6.58 9.08 114.72

6 20b EA 6.69 9.42 114.50

7 22a EA 5.91 7.95 74.45

8 22b EA 6.67 8.52 83.70

1 13c EE 6.34 10.02 44.06

2 13d EE 7.06 10.36 48.69

3 15c EE 8.59 9.94 36.65

4 15d EE 7.99 10.58 47.18

5 18c EE 6.22 9.49 50.83

6 18d EE 7.13 10.14 50.68

7 20c EE 6.32 11.32 45.66

8 20d EE 6.20 11.12 71.90

9 22c EE 8.53 10.67 33.41

10 22d EE 6.31 10.33 40.55

a

 Pñδ curve deflection error. 
9

Appendix CóTimber rivets in yellow poplar PSL 

No.

test

Ident.

no.

Nails/load

orientation

Yield load 

(×103

lb/in2

) 

Max. load

(×103

lb/in2

)

Slope

(×103

lb/in2

/in)

1 32a AA 6.85 10.19 136.05

2 32b AA 7.25 10.13 85.46

3 34a AA 4.11 8.33 66.65

4 34b AA 5.35 7.81 72.97

5 36a AA 6.20 10.54 76.30

6 36b AA 6.50 9.84 117.64

1 32c AE 9.94 10.58 25.67

2 32d AE 7.91 11.14 38.26

3 34c AE 7.29 10.80 34.35

4 34d AE 8.82 10.45 31.40

5 36d AE 7.93 12.46 44.56

1 42a EA 6.10 9.11 115.96

2 42b EA 5.71 8.77 86.79

3 45a EA 5.40 9.43 109.51

4 45b EA 5.73 9.48 111.25

5 48a EA 6.26 9.02 79.75

6 48b EA 7.27 10.05 71.93

7 50a EA 6.21 9.15 76.83

8 50b EA 5.86 8.96 80.83

9 53a EA 7.81 10.52 88.11

10 53b EA 6.40 9.60 77.05

1 42c EE 8.24 11.34 41.30

2 42d EE 8.21 10.65 44.29

3 45c EE 7.88 12.13 49.52

4 45d EE 8.85 10.88 34.75

5 48c EE 7.24 11.03 44.01

6 48d EE 7.37 10.14 38.78

7 50c EE 7.80 10.48 30.81

8 50d EE 7.18 10.73 39.11

9 53c EE 9.88 11.05 69.00

10 53d EE 7.27 10.39 44.82

Appendix DóTimber rivets in yellow poplar LSL 

No. 

test

Ident. 

no. 

Nails/load 

orientation

Yield load 

(×103

lb/in2

) 

Max. load 

(×103

lb/in2

) 

Slope 

(×103

lb/in2

/in)

1 66b EA 6.16 8.50 98.53 

2 66d EA 5.80 8.91 82.23 

3 69b EA 6.75 9.53 120.44 

4 71a EA 7.52 8.43 41.54 

5 71c EA 6.81 9.17 68.47 

6 73b EA 5.87 8.96 103.39 

7 73c EA 4.95 9.88 100.66 

8 73d EA 7.23 9.02 50.28 

9 75a EA 5.55 9.91 144.04 

10 75b EA 5.18 7.78 74.10 

11 75c EA 6.43 9.53 93.79 

12 75d EA 5.67 9.22 76.06 

13 77a EA 6.05 9.18 152.00 

14 77c EA 6.56 10.89 108.15 

15 77d EA 5.97 10.98 97.65 

1 68a EE 8.49 11.25 40.97 

2 68b EE 7.43 11.57 52.21 

3 68c EE 6.22 11.01 65.92 

4 72a EE 4.13 10.00 57.48 

5 72b EE 11.14 12.18 31.02 

6 72c EE 7.02 11.65 48.65 

7 72d EE 11.41 12.09 38.45 

8 74a EE 9.94 11.65 60.31 

9 74b EE 11.3 11.34 30.99 

10 74c EE 5.20 10.42 44.89 

11 74d EE 5.35 9.94 55.93 

12 76a EE 5.45 8.60 77.29 

13 76b EE 9.67 12.06 53.93 

14 76c EE 7.22 10.28 43.52 

15 76d EE 6.78 11.06 62.15