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Existing research on progressive collapse of building structures mainly focuses on concrete and steel frame structures. To investigate the progressive collapse resistance of high-rise reinforced concrete (RC) frame shear wall structures, two typical 15-story building models are designed with equivalent overall lateral resistance to seismic actions. However the structural layouts in resisting the lateral forces are quite different for the two buildings. Building A is a weak wall-strong frame structure whilst Building B is a strong wall-weak frame system. 3-D finite element models of the two structures are established using fiber beam and multilayer shell elements. The progressive collapse resistances of the frames and the shear walls in both structures are evaluated under various column (shear wall) removal scenarios. Results demonstrate that there is a difference in progressive collapse prevention performance for different structural layouts. The progressive collapse resistance tends to be inadequate for the strong wall-weak frame system. Such a system is subsequently redesigned using the linear static AP method proposed in GSA2003, through which the reliability and efficiency of the method is confirmed. The outcome of this study has provided a reference for progressive collapse prevention designs of typical and representative high-rise RC frame shear wall structures.

This article presents a nonlinear static pushdown analysis to evaluate the progressive collapse-resisting capacity curves of typical reinforced concrete frames under different deformations. Unlike the previous studies in which only a few typical columns, such as a column on the bottom storey, are removed, this study examines the column removal scenarios for various typical locations from different stories. The primary findings are as follows: (1) the Vierendeel action causes different internal forces in the beams of different stories, which reduces the progressive collapse resistance under the beam mechanism and delays the development of the catenary mechanism. This may result in the beams failing successively from one floor to another in a frame system, which differs from the theoretical assumption that the beams are damaged simultaneously on different floors; (2) seismic designs significantly improve the progressive collapse resistance under the beam mechanism, especially for lower stories. However such an improvement is less significant for the catenary mechanism and little improvement is found for the top regions of the frame structures. Furthermore, a nonlinear dynamic analysis is conducted to validate the predicted resistances of the reinforced concrete frames in satisfying the requirement of collapse prevention. The design parameters as specified in the existing codes are also discussed.