Effects of Simulation of Various Boundary Conditions on the Results of Seismic Evaluation：Case Study of Old Engineering Building at Chaoyang University of Technology

• Main Authors: Yi-Wen Zeng, 曾宜文
• Other Authors: Chih-Peng Yu
• Format: Others
• Language: zh-TW
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/11378081299486641265

碩士 === 朝陽科技大學 === 營建工程系碩士班 === 97 === Since 1975 Freeman introduced a prototype model of the capacity spectrum method, Capacity Spectrum method has been widely used in the seismic assessment of reinforced concrete. This is especially true after Mahaney and others proposed ADRS format in capacity spectrum method in 1993. Over the years, there are many related researches by domestic researchers and yet seldom addressed the effect of the boundary modeling on the evaluation results. Therefore, through the case study of old engineering building at CYUT, the aim of this work is to investigate the degree of influence due to boundary modeling on the Seismic Capacity Evaluation. In this study, the lateral boundary conditions are modeled by walls, springs, and fixed supports , while the lower part of the boundary conditions, namely the foundations, are simulated as piles (members on elastic foundation), equivalent springs with soil stiffness, and rigid connections. Push-Over analyses are first carried out for various structural models with different boundary conditions at both lateral and foundation interfaces. Capacity curves can thus be obtained and converted to capacity spectra. Finally, corresponding acceleration of Seismic capacity can be determined by finding the maximum spectral acceleration or displacement of the spectra. The major findings based on the simulation results are as follows. For structures rested on normal to hard soil, the responses are so close to those associated with fixed supports that they can be modeled as fixed structures for simplicity. On the other hand, lateral boundary conditions significantly alter the result of seismic capacity on the target structure, and thus they are required to provide appropriate results. However, the results indicate that simulations based on shear wall elements and equivalent springs are more suitable selections since models with laterally rigid supports seem leading to over-estimated capacities