地震动设计反应谱特性对进水塔增量动力分析结果的影响研究

Study on influences from characteristics of ground motion design response spectrum on incremental dynamic analysis of intake tower

汶川地震后相关部门结合震害调研和抗震经验对水工建筑物抗震设计规范进行了修编,标准设计反应谱曲线下降段指数由0.9调整为0.6,场地类别及其相关的反应谱特征周期有所调整。根据新老抗震设计规范的不同规定,对我国西南某水电站进水塔进行增量动力分析,研究比较新老标准设计反应谱特性的变化对进水塔增量动力分析结果的影响。研究表明,根据旧规范DL 5073—2000,满足最大设计地震要求的进水塔抗震能力为0.299 g,而根据新规范NB 35047—2015,抗震能力为0.192 g,降低了35.8%。因此,标准设计反应谱特性的变化对进水塔增量动力分析结果的影响显著。研究结果可为水工抗震规范的应用和工程抗震设计提供有益的参考。

Due the revision of the specification for seismic design of hydraulic structure made by the relevant department in combination with the post-investigation of earthquake and the earthquake resistant experiences after Wenchuan Earthquake, the index of the descending part of the response spectrum curve is adjusted from 0. 9 to 0. 6, while site types and their characteristic periods of the relevant response spectra are adjusted as well. In accordance with the different specifications defined in both the current and the previous design specifications, the incremental dynamic analyses are made on the intake tower of a hydropower station in the South- west China respectively, in which the influences from the variations of the characteristics of the design response spectra based on both the current and the previous standards on the results of the incremental dynamic analyses are comparatively studied. The study shows that the aseismic capacity for meeting the requirement of the maximum design earthquake is 0. 229 g according to the old specification of DL 5073-2000, however, the aseismic capacity is decreased by 35.8% and then is 0. 192 g according to the new specification of NB 35047-2015. Therefore, the influences from the characteristics of the standard design response spectra on the results of the incremental dynamic analyses of the intake tower are quite significant. The study result can provide beneficial refer- ence for the application of the specification for seismic design of hydraulic structure and the relevant aseismic designs.