Development of Nailed Wood Joint Element in ABAQUS

Testing showed that the hysteretic behavior of nailed wood joints governs the response of many wood systems when subjected to lateral loadings. Unfortunately, commercially available software does not have the appropriate hysteretic element for a nailed wood joint, and the accuracy and versatility of the previously developed nail joint elements are not satisfactory. A general hysteretic model, Bouc-Wen-Barer-Wen, was modified to represent the hysteretic behavior of a nailed joint, in which the hysteretic constitutive law is characterized by a series of ordinary differential equations. It can produce versatile and smoothly varying hysteresis curves, is nonlinear, history dependent, and includes stiffness and strength degradation, and pinching. Based on the test data, the suitable parameters for different joint configurations can be estimated through genetic algorithms. This model was embedded in commercially available software, ABAQUS/Standard (Version 6.5), as a user-defined element which accounted for the coupling property of the nail joint action. A detailed shear wall was modeled and analyzed, and the results agreed well with the test data.