Lessons from the Collapse of Typical RC Frames in Xuankou School during the Great Wenchuan Earthquake

Abstract

The seismic damage of typical reinforced concrete (RC) frames in Xuankou School during the Great Wenchuan Earthquake in China is introduced. A simulation method for the seismic damage sustained was developed to enable analysis of the damage mechanisms. The simulation makes use of different nonlinear finite element (FE) models, including macro-scale fibre-beam-element models and a micro-macro-scale hybrid model. The results of the nonlinear FE simulations show that the design of RC frames do not properly allow for the influence of slabs and footing rotations, which results in incorrect predictions of the internal forces and hence, the seismic damage. The collapse resistances of different buildings are compared using incremental dynamic analysis (IDA). The IDA results show that the collapse resistance of the classroom buildings is much lower than that of the office buildings because the larger axial load ratio in classroom buildings limits their lateral deformation capacity. An optimum design is proposed which would improve the collapse resistances of classroom buildings at very low cost.