A URBAN SEISMIC DAMAGE ANALYSIS MODEL FOR TALL BUILDING GROUPS

Tall buildings are very important parts of urban building groups and current building computational models are not able to meet the requirements of urban seismic analysis for tall buildings. In this work, a nonlinear multiple degree-of-freedom (MDOF) flexural-shear (NMFS) model and its corresponding parameter determination method are proposed. The model has the following advantages:1) Appropriate consideration of nonlinear flexural-shear deformation mode of tall buildings. Compared with traditional nonlinear MDOF shear (NMS) model, the accuracy is significantly improved and the response result agrees well with the refined finite element (FE) model; 2) High computational performance, which is more than 60000 times faster than the refined FE model; 3) Very convenient parameter determination. The nonlinear parameters of the model can be determined using limited building data (i.e., structural height, year of construction, site condition and structural type) of each building; 4) The ability to output time-history responses and inter-story drifts, which may facilitate the future engineering demand parameter (EDP) based loss estimation for tall building in urban area. In this study, a representative tall building is selected to demonstrate the modelling and parameter determination processes of the proposed NMFS model. Verifications are made by comparing with the refined FE model. Finally the method is used to perform the urban seismic analysis for the Central Business District (CBD) of Beijing, which proves the applicability of the method for tall buildings in urban area. Outcomes of this work are expected to provide a useful reference for future works on urban seismic loss estimation of tall buildings.