重力坝底孔坝段动力响应研究

Research on dynamic response of bottom intake section of gravity dam

以龙滩水电站大孔口底孔坝段为研究对象,建立三维有限元模型。基于ABAQUS用户子程序UEL成功地开发4节点单自由度用户单元,较好地模拟动水压力与大坝的相互作用,完成底孔进水口及底孔出口明渠导墙的动力特性分析,总结主振型规律,讨论动水压力附加质量对结构自振特性的影响。结果表明:在研究坝体地震响应分析时,应主要研究顺河水平向和竖向地震作用响应,内水模型对自振频率影响甚微,计算时可以不考虑内水压力附加质量。

Base on the bottom hole section of Longtan Hydropower Station,a three-dimensional FEM model was established.Making use of the user subroutine provided by ABAQUS,a user element with 4-nodes single freedom was developed successfully;and dam-reservoir interaction was simulated preferably.Then,the dynamic characteristics of inducing wall of open channel for the bottom intake and outlet were analyzed;the law of the main vibration mode was summarized,and how the added mass affect the vibration characteristics was discussed.It suggests that the main study should be on the direction of along the river and the vertical during seismic response analysis,and the inner water model have little effect on the natural frequencies,so the model can be simulated without the added mass of the inner water.