基于能量法的水电站厂房抗震性能分析

为了便于水电站厂房抗震性能评估与设计方案的比选,结合动力学和弹性反应谱理论,推导出了一种可以计算在地震作用下经地面输入到水电站厂房结构的总输入能的能量计算公式。通过该公式分别分析了水电站厂房结构自振特性、场地地基条件、地震动参数等多个因素对厂房输入总能量及抗震性能影响的敏感性,对不同设计方案的抗震性能做出评判。算例分析表明,通过对比能量公式与反应谱分析的计算结果可知,利用能量法进行抗震方案比选和优化设计简易有效。该方法可快速简便的计算出地震输入到水电站厂房结构的总能量,可同时分析多个因素变化对厂房能量的影响,且结构自振特性、场地地基条件和地震动参数对厂房输入总能量及抗震性能的影响规律具有普适性,可为水电站厂房及类似工程抗震设计提供参考。

Energy approach-based analysis on seismic performance of powerhouse of hydropower station

In order to be convenient for the assessment made on the seismic performance of the powerhouse of hydropower station and the comparative selection of the relevant design schemes，an energy calculation formula which can calculate the total input energy that is input into the structure of powerhouse of hydropower station through ground surface under seismic action is educed. With this formula，the sensitivities of the influences from several factors such as self-vibration characteristics of the powerhouse， the insitu foundation condition，the seismic dynamic parameters，etc. on the total input energy into the powerhouse and its seismic performance are analyzed herein，and then the seismic performances of various design schemes are evaluated. The analysis on the calculation case shows that it is known that the energy approach is simple and effective for carrying out the comparative selection of aseismic schemes and the optimization of design through comparing the calculation results from both the energy formula and the response spectrum analysis. This method cannot only rapidly and simply calculate the total energy input into the powerhouse structure from earthquake，but also can simultaneously analyze the influences from several factors on the energy input into the powerhouse，thus the laws of the influences from structural self-vibration，in situ foundation condition and seismic dynamic parameters are generally applicable，and then can provide references for the aseismic designs of the powerhouse of hydropower station and the similar project concerned.