DECISION-MAKING ANALYSIS OF UNIFORM COLLAPSE RISK FOR RC FRAME-SHEAR WALL STRUCTURES

The decision of target collapse risk is one of key scientific problems in uniform-collapse-risk seismic design of building structures. Reinforced concrete (RC) frame-shear wall structures are taken as research objects. By employing the second-generation performance-based earthquake engineering (PBEE) framework and methodology, the earthquake losses are evaluated for five 12-story RC frame-shear wall structures with different fortification levels, and then the direct economic losses, downtime and casualties are uniformly monetized. According to the principle of the minimum total life-cycle economic cost during the design period, the uniform collapse risk of RC frame-shear wall structures is determined. The results of the study show that the uniform collapse risk of RC frame-shear wall structures with different fortification levels is 0.26% over 50 years (equivalent to an average annual collapse probability of 5.26×10⁻⁵), which is extremely close to the European consensus collapse risk whose uniform collapse target is 0.25% over 50 years. It proves the rationality of this decision-making method and the accuracy of the decision-making results. The decision results of this paper can provide theoretical foundation for risk-targeted seismic ground motion parameter mapping and uniform-collapse-risk seismic design of structures.