摘要
水利枢纽多建在西部等强震地带,高坝的抗震安全性是无法回避的问题,为反映特定地震特性和场地影响,模拟地震波从震源激发到介质传播再到场址的过程,构建了震源-传播介质-场址的谱元法数值模型,进而生成工程所需的地震动参数。震源模型采用运动学震源,采用有限断层的方法离散成若干子源,利用数据融合的方法构建溪洛渡地区的非均匀介质波速结构;利用高精度的地形数据以考虑复杂局部场地峡谷地形,并选取永善县的实际地震将实测值与模拟结果进行了对比,验证了模型的合理性和精度。最后根据溪洛渡区域的实际地质断层信息,确定潜在震源位置,考虑最不利的情况来确定震源深度、滑移量分布、起始破裂点位置,对溪洛渡近场潜在地震进行模拟,比较场址的地震动特征,最终确定对溪洛渡拱坝影响最大的震源为雷波断裂中支所在的潜源。
The seismic safety of high dams is a inevitable problem for water conservancy projects to be built in strong earthquake areas such as the west.In order to reflect the specific seismic characteristics and site influence,a spectral element numerical model of seismic source-medium propagation-site is constructed to simulate the process of seismic wave from source excitation to medium propagation and then to site,and then the ground motion parameters required by the project are generated.The seismic source model adopts kinematic source,the source is dispersed into several sub-sources by using finite fault method,and non-uniform medium wave velocity structure in Xiluodu area is constructed using data fusion method.The high-precision topographic data is used to consider complex local site canyon topography,and the actual earthquake in Yongshan County is chosen to compare the measured values with the simulated results,which verifies the rationality and accuracy of the seismic source model.Then,according to the actual geological fault information in Xiluodu area,the potential near-field earthquakes in Xiluodu are simulated after determining the potential focal location,and determining the focal depth,slip distribution and initial rupture point considering the most unfavorable situation,and the ground motion characteristics of the site are compared.Finally,it is determined that the source with the greatest influence on the Xiluodu arch dam is the latent source where the middle branch of the Leibo fault is located.
作者
彭志豪
徐艳杰
侯信超
时洪涛
黄海龙
PENG Zhihao;XU Yanjie;HOU Xinchao;SHI Hongtao;HUANG Hailong(Department of Hydraulic Engineering,Tsinghua University,Beijing 100084,China;Guangdong Poly Real Estate Development Co.,Ltd.,Guangzhou 510308,Guangdong,China;China Three Gorges Construction Engineering Corporation,Chengdu 610000,Sichuan,China)
出处
《水力发电》
CAS
2024年第12期44-50,共7页
Water Power
基金
国家自然科学基金资助项目(52192672)
中国长江三峡集团有限公司科研项目(XLD/2117)。
关键词
谱元法
波场模拟
震源机制
最大可信地震
溪洛渡拱坝
spectral element method
seismic wave field simulation
focal mechanism
maximum credible earthquake
Xiluodu Arch Dam
