古田地震水口水电站重力坝强震观测记录的谱结构特征  

Spectral Structure Characteristics of Strong Motion Observation Records of Gravity Dam of Shuikou Hydropower Station in Gutian Earthquake

作　　者：郑师春[1] 张锦福[1] 赵志伟[1] 连玉平[1] 

机构地区：[1]福建省地震局,福建福州350003

出　　处：《华南地震》2010年第1期68-75,共8页South China Journal of Seismology

基　　金：地震科技联合基金资助105087

摘　　要：通过对水口水电站重力坝强震反应台站在古田地震中获取的强震反应观测资料进行信噪比、反应谱和功率谱分析,得到如下结论:①大坝在0.7～15 Hz频率段的振动特性较为可信;②坝基和自由场输入地震动富于高频,峰值加速度反应谱存在较大差异;③坝基输入地震动存在差异性,建议今后此类大坝抗震设计时考虑多点地震动输入;④单个卓越频率携带的能量对反应谱影响不大,反应谱是和输入地震动总能量相关的;⑤坝体刚度较大,此次地震中还处于线弹性状态。初步了解了强震记录的地震动特性和大坝结构的抗震性能,对认识水库地震近场地震动特性和重力坝地震反应有一定的参考意义。Based on the of strong motion response analysis on signal noise ratio, response spectrum and power spectrum observation data recorded by strong motion response array of gravity dam of Shuikou Hydropower Station in Gutian Earthquake, Conclusions can be drawn as follows： 1） the vibration characteristic is fairly reliable when frequency segment of dam is between 0.7-15 Hz. 2） the input ground motion of dam foundation and free-field are rich in high frequency, and there is great difference in response spectrum of peak acceleration between them ; 3） there exist difference in the input ground motion of dam foundation, so muhipoint seismic input can be taken into account in the future seismic design of such dams; 4） the energy carried by individual dominant frequency only has little influence on response spectrum which is exactly related to the total energy of input ground motion; 5） the dam body with comparatively large rigidity is still in the linear elastic state in this earthquake. We preliminarily understand the characteristic of ground motion of strong motion records and seismic behavior of dam structure, which can provide some reference to the understanding of characteristics of near-field ground motion of reservoir earthquake and seismic response of gravity dam.

关 键 词：功率谱 古田地震 水口水电站重力坝 反应谱 谱结构特征 

分 类 号：P315.914[天文地球—地震学]