Seismic Analysis Of Frame-shear Wall Structures Subjected To Near-field Earthquake Ground Motions

In recent years, rare earthquakes occurred more and more frequently. From the Northridge, Kobe, Chi-Chi earthquake in last century to 5.12 Wenchuan earthquake in China 2008 and the 9.0-magnitude quake in Japan this year, a large number of casualties and property losses cost. It should be noted that of those quakes were located near the faultage which made them fall into the near-field earthquake category. With the first velocity pulse of earthquake recorded thirty years ago, the research of near-field ground motion has made some achievements and keeps improving day by dag. However, the study of the damage level of forward-directivity and fling-step effects on the structure, and the seismic response of structure haven't come to a conclusion which can be used as guideline of design. At least, there is no detailed prescription of structure in near-field earthquakes in design code of China. With the development of technology, the height of structure has kept increasing which leads to high-rise structures becoming the major form of future buildings. In addition, the frame-shear wall structure has become the first option of current high-rise structures. The frame-shear wall structure is the first choice for current high-level structure. The responses of frame structure in the near-field earthquake have been studied much nowadays; however, few research about frame-shear wall structure has been made. Based on limitation mentioned above, researches focused on frame-shear wall structure have been made by this paper.1 Selecting obviously recorded seismic velocity pulse by analyzing amount of near-field seismic records, comparing acceleration response spectrum of various seismic records. Pointing out the necessity of modify the code of Chinese structure design by adding the near-field response spectra.2 Using MIDAS/building finite element software study the time history analyze. The effective of finite element software was proved by framework structure and the frame-shear wall model verification. Specifically describing the nonlinear element model of beam, column and shear walls used in the MIDAS / Building.3Through the far-field, near-field triple spectrum, analysis of 24 earthquake waves, the characteristics of the near-field ground motion and the response spectrum had been further studied. Besides, qualitative analysis and description of the near-field seismic response of the three frame-shear wall structures studied in this paper had made.4 The dynamic responses of near-field velocity pulse under earthquake of three frame-shear wall structures (13 layers, 18layers, 23layers) was studied in this paper. The seismic response under the near-fault ground motions of the frame-shear wall structure has been studied in three aspects: the calculated response, the distribution of plastic hinges and the internal force response. Comparison of near-field forward-directivity effect, fling-step effect and structural dynamic response under far-field earthpuakes had been made.