roof framing connections in conventional residential construction

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configuration. For test configuration 2 with three 8d nails per connection, five of the specimenswere tested with two nail heads facing up and five were tested with one nail head facing up andthe results were averaged. The averaging was justified because there was little differenceidentified in the peak load between the two loading configurations. These component testspecimens differed from system test conditions in that the toe-nails were not located near thebeveled end of the truss chord member. But, this component test condition was consistent withthe NDS provisions for use of the toe-nail factor, K tn .4.3.3 Results and DiscussionTwo configurations of individual roof-to-wall connections were tested in correspondence withroof system test configurations 1 and 2 (Table 16) with two 16d pneumatic nails and three 8dcommon nails per joint, respectively. Figures 24 and 25 display the load-displacement curves forthe individual toe-nailed connections. Table 19 summarizes results of the testing.700600500400Load, lb30020010010 curves00.0 0.2 0.4 0.6 0.8 1.0Slip, inchFigure 24Load-Slip Relationships for Individual Roof-to-Wall Toe-Nail Connections Assembled with2-16d Pneumatic Nails – Configuration 140
700600500400Load, lb30020010010 curves00.0 0.2 0.4 0.6 0.8 1.0Slip, inchFigure 25Load-Slip Relationships for Individual Roof-to-Wall Toe-Nail Connections Assembled with3-8d Common Nails – Configuration 2TABLE 19RESULTS OF INDIVIDUAL ROOF-TO-WALL TOE-NAILED CONNECTION TESTSCONFIG. #12CONNECTION2-16d pneumatic nails (toenailed)3-8d common nails(toe-nailed)SAMPLESIZEAVERAGEAVERAGE PEAK LOAD,DISPLACEMENT @ PEAKLBLOAD, INCHMean COV, % Mean COV, %10 499 19.4 0.498 49.510 449 15.9 0.380 52.4The statistical analysis of variance (ANOVA) showed that the average peak loads of theconnections assembled with 2-16d pneumatic (499 lb) and 3-8d common (449 lb) nails were notsignificantly different (P-value = 0.20 > 0.05). This finding confirmed the results of the full-scaleroof system tests that also identified only a marginal difference in the average peak loadsbetween these two nailing schedules (Table 16). The coefficient of variation for displacement atpeak load of about 50 percent for both connections indicated high variability of stiffnesscharacteristics for individual toe-nailed connections.Table 20 includes the NDS allowable lateral design values for toe-nailed connections and theexperimental average loads at 0.015-inch joint slip. Similarly to the results of heel joint tests(Section 4.2), the NDS allowable lateral design values overestimate the connection resistance atthe 0.015-inch slip limit state. Furthermore, the disparity between the calculated and measuredvalues is increased for toe-nailed connections as compared to face-nailed connections (Table 10)by as much as a factor of two. This effect can be explained with the change in failure modesfrom primarily lateral response of face-nailed connections to a combined lateral and withdrawalresponse of toe-nailed connections.41
Page 2 and 3: PATH (Partnership for Advanced Tech
Page 9 and 10: LIST OF TABLESTable 1 - Selected Re
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Page 14 and 15: Section 3. Section 4 includes three
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Page 19 and 20: TABLE 1SELECTED RESISTANCE DATA FRO
Page 21 and 22: Uplift tests were conducted on toe-
Page 23 and 24: Table 3 summarizes specific gravity
Page 25 and 26: connections. Test results were used
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Page 41 and 42: double top plate was fastened to th
Page 43 and 44: TABLE 16SUMMARY OF TEST RESULTS FOR
Page 45 and 46: Figure 16Truss Separation from Top
Page 47 and 48: Table 17 compares the experimental
Page 49 and 50: Maximum 0.2 sec design spectral res
Page 51: TABLE 18SPECIMEN CONFIGURATIONS FOR
Page 55 and 56: Figure 26Toe-Nailed Joint ResponseT
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Page 59 and 60: [7] Wilkinson, T. L. 1993. Bolted C
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