Seismic Damage‐Control Design of Gypsum‐Roof Diaphragms

Abstract

A comprehensive experimental, analytical, and parametric investigation of the performance of gypsum‐roof structures under severe earthquake excitations is presented. Force‐deformation hysteresis were obtained from laboratory tests of typical gypsum panels to characterize the cyclic behavior of gypsum. The tests were also used to distinguish two levels of seismic performance: damage control and life safety. A special hysteretic model was developed to model the degrading behavior of the gypsum diaphragm. The model was incorporated into a special‐purpose computer program with the ability to model inelastic in‐plane diaphragm flexibility. The program was used to perform complete stiffness‐degrading inelastic analysis of typical gypsum‐roof structures subjected to a variety of accelerograms. The ensuing parametric study was directed at identifying a damage‐based criteria for both the design of new structures and the retrofit of existing structures.