Research On Computer Simulation Of Typical Seismic Damage To Steel Frame Structures

In the Northridge earthquake in 1994 and the Kobe earthquake in 1995, widespread and unpredicted brittle fractures were found in weld steel beam-column connections (weld-flange-bolted-web connections). The research on behaviors of beam to column connections has been a hot spot in the recent several years. Software and hardware for computers are developing at very fast speed. It creates a condition of computer simulation of seismic damage to steel frames. Computer simulation of earthquake response can provide a powerful tool for seismic research. Computer simulation of earthquake response of steel frames can provide a basis for seismic design of steel frames. Computer simulation has important meaning to seismic strengthening and seismic damage prediction.Fractures in the weld root on column fusion face are typical earthquake damage to steel frames. The object of this paper is computer simulation of typical seismic damage to steel frame structures. The stiffness, strength and behavior of different kinds of beam-column connections were investigated. Finite element analyses were used to study fracture toughness in welded beam-column connections. The influence of concrete slabs on behavior of beam-column connections was also investigated. A simplified model was developed to simulate seismic damage to steel frames.The main contests and conclusions are listed as follows:1 The failure modes and location of steel frame were analyzed under static loads. The failure modes included strength failure and stability failure. The failure modes of steel frame were introduced under earthquake loads. The reasons of earthquake failures were analyzed. Gravity and seismic moments on connection were compared. Results show that low-rise steel frame structures can ignore fracture of bottom beam flange in the low seismic intensity area.2 Build up the finite element model. Through comparing the shell element result to the test result, it proved feasible in shell element model to get the behavior of beam-column connections under monotonic and cyclic loads. Through comparing the solid element result to the test result, it proved exact in the solid element model to get the behavior of weld-flange-bolted-web...