Estimation of allowable resistance of nailed shear walls considering the variance of nailed joint resistance

The lateral resistance of nailed joints with wood-based panels generally ha s a large variance. The resistance of nailed shear malls, on the other hand , has less variance than single-nail joints. This is because they are assem bled with many nails, which results in a multiple member effect. It may the refore be too conservative to use the fifth percentile lower limit resistan ce of nailed joints, which is commonly adopted in determining their allowab le resistance, to estimate the allowable lateral resistance of the nailed s hear walls. Some numerical simulations were conducted on the nailed shear walls with OS B sheathing panels to find a reasonable way of estimating their lateral res istance based on the load-slip properties of single-nail joints. The numeri cal simulations were carried out by two methods: 1) a Monte Carlo simulatio n using the load-slip curves randomly generated by an empirical equation fi tted to the test results of the single-nail joints, and 2) a numerical simu lation using the definite load slip curves which corresponded to the fifth, tenth, twentieth, thirtieth, fortieth and fiftieth percentile lower limits . The simulated results were compared with the results of full-scale tests of nailed shear walls. The Monte Carlo simulation, particularly by the first method, gave a reasonable distribution of the lateral load-deformation curv es of the shear walls up to their maximum loads. It could not cover, howeve r, their entire load-deformation behavior including the brittle, sudden dro pping of loads observed in the full-scale tests. The numerical simulation using the thirty-fifth percentile lower limit load -slip curves of the single-nail joints gave a conservative estimation of th e fifth percentile, lower limit load-deformation curves of the nailed shear walls.