Research On The Hysteretic Energy Dissipation-based Pushover Analysis Method

Presently, the seismic design has been shifted from force-based design to performance-based design or displacement-based design. As the development trend of earthquake engineering, the basic ideal of performance-based seismic design will be used as the design criterion and applied to the present projects. Meanwhile, the performance-based seismic design is based on the reliability theory. As an important tool of the performance-based design, improving the computation precision of Pushover analysis and making a probability investigation to the analysis results are the research hotspots. The research contents developed mainly in the thesis are as follows:1. The thesis put forward the adaptive hysteretic energy dissipation-based push- over analysis method. The 335 seismic waves collected are divided into groups on the basis of the field sort etc and the corresponding hysteretic energy dissipation spectra are established. Based on the modal pushover analysis given by Chopra and the energy-based drift given by Aschhein, the energy-based drift is imported into the Pushover analysis with hysteretic energy spectra, and the higher modes are taken into account with the adaptive horizontal loading pattern. In the thesis, the frame members are simulated with five subsection model. Fortran90 is used to programme for the Pushover analysis considering five different loading patterns such as hysteretic energy-based, inverted triangular distribution etc. and SAP2000 is used for the time history analysis. Lastly, two numerical examples demonstrate that the feasibility of the method in the thesis.2. With the safe margins analysis based on the intensity failure of the structural system, the limit state equation of the capacity curve from Pushover analysis is built. Taking the emergence order of plasticity ream from the static inelastic analysis as the dominant failure modes and taking account of the effects of different loading patterns on the randomicity of the capacity curve. The main affecting factors are obtained with the analysis of sensibility factors. Meanwhile, taking account of the randomicity of the structures and the earthquake action, an computing method for the guaranteed rate of the capacity curve based on the hysteretic energy-based Pushover analysis is given in the thesis.3. The random sampling is used to the main affecting factors of the capacity curve, and the direct important sampling is used to the limit state equation of the structure system. The computing precision is verified by the two numerical examples. It is concluded that the proposed method for the guaranteed rate generally has satisfactory precision.