基于功能的混凝土重力坝抗震风险模型研究

Performance-based aseismic risk analysis model of concrete gravity dams

抗震风险评价是基于功能的抗震设计的关键问题之一。通过对大坝可能出现的抗震风险进行分析论证,在技术和经济上进行风险评估,为大坝业主提供决策依据,也可对抗震风险提出优化措施或对策。在重力坝抗震风险分析中,采用已给出的抗震破损程度划分标准,利用地震危险性分析和坝体地震易损性计算,建立了抗震风险分析模型,进行了抗震措施分析。通过金安桥混凝土重力坝抗震风险实例研究,计算得出抗震优化前后的风险概率,说明了抗震风险模型可用于混凝土重力坝的抗震风险评价。

Risk evaluation of concrete gravity dams subjected to strong earthquake is one of the key problems of performance-based aseismic design. Risk assessment in view of technology and economy is on the base of decision-making, and aseismic optimization are put forward. By using classification criterion of destroyed degree due to strong earthquakes given by researchers, earthquake hazard and aseismic fragility assessments of dam, aseismic risk model is established; and aseismic countermeasures are analyzed. The Jin＇anqiao Concrete Gravity Dam under construction is taken as the example for illustrating the risk assessment. It is shown that the model is basically applicable to risk assessment of concrete gravity dams subjected to earthquakes.