Probabilistic-based Seismic Assessment For Gallery Single-bay School Buildings

Performance-based earthquake engineering has been developed into the widely-accepted first generation design theory during the last two decades. To overcome the deficiencies of the first generation performance-based design, Pacific Earthquake Engineering Research center proposed a seismic assessment framework based on the total probability theory. The framework fully consider the uncertainties in the seismic assessment, and measure the buildings seismic performance in probability method, forming the next-generation performance-based seismic design theories. This paper describes the second generation performance-based seismic design framework and calculation process.After the Wenchuan earthquake, the seismic design level of the school building was improved according to the national seismic design code of buildings, and many existing school buildings need to perform the seismic assessment and to be retrofitted. To simplify the loss evaluation process, this paper uses the fuzzy decision theory to calculate the earthquake loss, and combines it with the second generation performance-based assessment process, applying in the evaluation of the seismic performance of a gallery single-bay structure under severe earthquake. In addition, the algorithm generating the related engineering demand parameters in the evaluation process is improved to make it applicable to a variety of distributions.Three reinforcement schemes were proposed in this paper for the gallery single-bay structure, installing the buckling restrained brace, short-leg shear wall, and damper. Loss evaluation was carried out and the loss distribution of each scheme was obtained. Finally, cost-benefit analysis is conducted for the scheme of buckling restrained brace, and the return rate of the scheme is obtained. The probability-based assessment method for buildings design or retrofitted is instructive.