The risk-based assessment, also called time-based assessment of structure is usually performed to provide seismic risk evaluation of a target structure for its entire life-cycle, e.g. 50 years. The prediction of collapse probability is the estimator in the risk-based assessment. While the risk-based assessment is the key in the performance-based earthquake engineering, its application is very limited because this evaluation method is very expensive in terms of simulation and computational efforts. So the evaluation database for many archetype structures usually serve as representative of the specific system. However, there is no such an assessment performed for building stocks in Korea. Consequently, the performance objective of current building code, KBC is not clear at least in a quantitative way. This shortcoming gives an unresolved issue to insurance industry, socio-economic impact, seismic safety policy in national and local governments. In this study, we evaluate the comprehensive seismic performance of an low-rise residential buildings with discontinuous structural walls, so called piloti-type structure which is commonly found in low-rise domestic building stocks. The collapse probability is obtained using the risk integral of a conditioned collapse capacity function and regression of current hazard curve. Based on this approach it is expected to provide a robust tool to seismic safety policy as well as seismic risk analysis such as Probable Maximum Loss (PML) commonly used in the insurance industry.

The collapse probability of a structure designed according to the current domestic seismic design code, KBC 2009 is evaluated by the risk integral which simultaneously considers the seismic hazard curves and the probabilistic distribution of a structural collapse capacity. The evaluation shows that the prototype frames considering in this paper present different collapse probabilities in 50 years according to the heights and locations, although they are designed according to the same design requirements for steel intermediate moment resisting frames prescribed in KBC 2009.

The purpose of this study is to evaluate the collapse probability of structural member in building. Probability of material strength and live load were collected. By evaluating the probability distribution for design strength and required strength, the probability on the collapse of a column were evaluated.