PREDICTING THE STRENGTH OF WOOD-JOIST FLOORS.

Light-frame wood-joist floors are complex structures, and interactions among the parts of such floors are as complex as those in any structure. The stiffnesses of various parts of the floor and their contributions to the stiffness of the floor as a whole are an important set of interactions in determining the structural performance of such systems. These interactions are nearly linear as service loads; thus linear models now used, such as FEAFLO (Finite-Element Analysis of FLOors) (Thompson and others 1977), are useful in predicting the performance of floors within the service load range. However, linear models are less useful in predicting the performance of floors under greater loads. The research in this study used one option of the computer program NONFLO to accommodate the nonlinear load-slip characteristics of the nails. This option is a nonlinear analysis with a searching algorithm to determine the failure load while simultaneously satisfying equilibrium and compatibility at impending failure. Refs.