空间相关非平稳地震荷载作用下的大坝风险分析

Risk Analysis of Dams Under Spatial Correlative Non-stationary Seismic Load

坝体风险性研究具有十分重要的意义。文章提出了在空间相关非平稳地震荷载作用下,不同破坏模式下的大坝风险分析系统分析方法。首先采用人工生成空间相关非平稳地震动时程和Mazars混凝土损伤模型,通过对混凝土重力坝的坝头、上游折坡面以及建基面等处的损伤值及其抗滑稳定系数的研究,然后推导了大坝溃口宽度以及相应的溃口流量随时间的变化规律,根据溃口时间和流量变化推出了溃坝后的生命损失以及财产损失,最后进行了算例分析。通过计算结果可以看出,所提出的模型能够考虑大坝的风险发生的各个过程,并能够较全面的描述大坝的风险。

The risk analysis for dams is of great significance .The systematic risk analysis method for dams of different failure modes subjected to spatial correlative non-stationary seismic load was put forward .Firstly ,the time histories of the earthquake ground motion with the spatial correlation and non-stationarity characteristics were synthesized and the Mazars damage model was adopted to define damage value and anti-sliding stability coefficient of the dike head ,upstream gradi-ent surface and foundation surface of the gravity dam .Then ,the calculation method for the time of dam burst and the variations of breach flow was derived to analyze life and property loss .At last an example was applied to varify the appli-cability of the damage model .The results indicate that the proposed model can simulate every process of dam risks and roundly describe the integrity of dam risks .