考虑螺栓滑移效应的角钢输电塔抗震性能研究

Study on the Seismic Performance of Angle Steel Transmission Towers Considering the Bolt Slippage Effect

为研究螺栓滑移效应对角钢输电塔抗震性能的影响,利用ABAQUS有限元软件中的非线性弹簧模拟角钢输电塔节点的刚度特性,建立考虑螺栓滑移效应的角钢输电塔有限元模型,基于数值模型开展角钢输电塔的动力特性、地震响应、失效倒塌和地震易损性分析.结果表明:考虑螺栓滑移效应后,角钢输电塔的振型不变但各阶自振频率有不同程度的降低,说明在传统设计方法中高估了角钢输电塔的整体刚度.考虑螺栓滑移效应后,角钢输电塔在地震作用下的主材轴力响应、塔身位移响应和易损性增加,其失效机理和倒塌形式也发生改变.在抗震设计中考虑螺栓滑移效应的影响有助于准确预测角钢输电塔的失效位置,对保障震区输电线路的可靠性与安全性有重要意义.

To investigate the impact of bolt slippage on the seismic performance of angle steel transmission towers,this study utilized non-linear springs in ABAQUS finite element software to simulate the stiffness behavior of angle steel transmission tower joints.A finite element model was established for angle steel transmission towers,considering the effects of bolt slippage.Based on the numerical model,dynamic characteristics,seismic response,failure collapse,and seismic susceptibility of angle steel transmission towers were analyzed.The results indicate that,after considering the bolt slippage effect,the vibration pattern of the tower remains unchanged,but the self-oscillation frequency of each order is reduced to varying degrees.This suggests that the overall stiffness of the angle steel transmission tower is overestimated in the traditional design method.Moreover,the main member axial force response,tower displacement response,and seismic susceptibility of angle steel transmission towers under seismic action increase,and the failure mechanism and form of collapse also vary.Considering the impact of bolt slippage in seismic design can aid in accurately predicting the failure location of angle steel transmission towers,which is of great significance in ensuring the reliability and safety of transmission lines in earthquake-prone areas.