型钢混凝土闸墩的地震谱分析

Analysis of seismic spectrum of steel reinforced concrete pier

为了研究型钢混凝土闸墩的地震反应,以邕宁水利枢纽型钢混凝土闸墩为基础模型,借助ANSYS软件,采用水工抗震规范中的主流地震谱分析方法,获取用于水闸地震响应求解的设计反应谱,使用振型分解法求解型钢混凝土闸墩的地震响应.结果表明:型钢混凝土闸墩自由振动的主要形态是墩体横水流方向的左右平动,基本周期约为0.7s;型钢混凝土闸墩的自振频率间隔较大,频率自小向大的排列属于稀疏型频率谱;地震引起的型钢混凝土闸墩变形不大,但是局部应力偏大会导致闸墩开裂,这与水利工程震害调查中闸墩常见的开裂破坏较为吻合.

In order to study the seismic response of steel reinforced concrete pier, this paper takes the steel concrete pier of the Yongning Water Conservancy Project as a basic model, with the help of the ANSYS software and using the mainstream seismic spectrum analysis method in hydraulic seismic codes to get the design response spectrum for the sluice seismic response solution;and then using the vibration mode decomposition method to solve the seismic response of the steel concrete pier.The results show that the main form of free vibration of the steel concrete pier is the left and right translation of the lateral flow direction of the pier;and the basic period is about 0.7 s;the free vibration frequency spacing of steel-reinforced concrete pier is large, and the frequency from small to large is a sparse frequency spectrum;the deformation of the steel-reinforced concrete pier caused by the earthquake is not large,but the partial stress tends to cause cracking of the pier, which is consistent with the common cracking damage of the pier in the seismic damage investigation of hydraulic engineering.