| The traditional seismic design method, combined with structural measures, can realize the seismic fortification goal and ensure the safety of life under earthquake. However, nowadays earthquake causes fewer casualties but huge financial loss. Performance based seismic design can achieve different performance objectives, which are quantified according to the site engineering condition and the importance of the structure. This method pays attention to the performance of the structure in elastic state and plastic stage, and can attain the development of plasticity and weak part of the structure under severe earthquake.Steel frame-RC core wall hybrid structure combines the high strength of steel structure and the high stiffness of RC core wall. It is widely used in high-rise building. But it has not been widely acknowledged yet and the problem of "Multiple anti-seismic lines of defence systems" needs further investigation.The theory of performance-based seismic design method is introduced in this paper, and, on the basis of a certain project, the enforcement methods of this seismic philosophy, including selection of performance objectives and structural analysis and distinction of performance levels, is carefully studied.Based on ETABS software and SATWE software, the response spectrum analysis and elastic tine-history analysis under frequent earthquake are carried out. The results, including seismic force, deformation and damage of structure are obtained. Most of the seismic performance indicators meet the requirement of the Code. The lateral stiffness of the three layers at the bottom is weak, and the torsional deformation is significant.Midas software is used to carry out the Pushover analysis. The development of plasticity is observed and seismic shear, displacement and damage of the structure are obtained. The results show that the seismic of the structure under severe earthquake meet the requirement of the Code, and that the damage states of the structure meet the selected performance objectives.The original structure scheme is optimized, after a careful analysis of the characters of the structure. The response spectrum analysis is conducted on the optimized design to compare its seismic performance with that of the original structure. The cross-sectional dimension of the shear wall of the optimized structure is smaller, the cost is reduced, and the seismic performance is excellent. A new kind of composite slabs, steel truss deck, is used in the structure. Through comparative study of the steel truss deck and the formed steel deck, the features of these two composite floors are introduced. Based on the project, two kinds of slab are designed respectively. Cost analysis of each design is carried out, and application proposals are put forward. |
