考虑结构与加锚岩体联合受力的船闸闸首抗震性能研究

为研究地震作用下结构与加锚岩体的非线性接触对闸首抗震性能的影响,以某双线五级船闸的第一级闸首为例,在ADINA有限元软件中建立库水-结构-锚杆-基岩动力相互作用的整体三维有限元模型,基于约束函数的非线性接触单元模拟了闸首结构中的各类接触问题,采用动力时程分析方法模拟了地震作用下闸首结构的动力响应、锚杆受力的分布规律以及不同接触面的接触状态。结果表明:设计地震作用下闸首各边墩均向航槽侧变形,位移沿高度方向递增；锚杆轴向拉应力的最大值小于其抗拉强度；不同介质间的接触面上部有往复开合的现象,接触面最大张开度沿高度方向递增,地震结束时接触面恢复到震前的紧贴状态；设计地震作用下该船闸闸首的结构变形、结构应力、锚杆受力情况及接触面接触状态均满足规范要求,具有良好的抗震性能。

Study on seismic performance of a lock head considering combined force of structure and anchored rock mass

To study the influence of nonlinear contact between structure and anchored rock mass on the seismic performance of a lock head under earthquake, taking the first stage lock head of a double-line five-stage ship lock as an example, a three-dimensional finite element model for the dynamic interaction of reservoir water-structure-anchor-bedrock was established in the finite element software ADINA. The various contact problems in the lock head structure were simulated by the nonlinear contact elements based on constraint function. The dynamic responses of the lock head structure, the distribution law of the anchor force, and the contact state of different contact surfaces under the design earthquake were analyzed by time-history analytical method. The results show that the piers on each side of the lock head are deformed to the side of the navigation channel under the design earthquake, and the displacement increases along the height direction. The maximum axial tensile stress of the anchor is less than its tensile strength. The upper parts of the contact surfaces between different contact pairs are repeatedly opening and closing. The maximum opening of the contact surface increases with elevation. At the end of the earthquake, the contact surface is restored to the state before earthquake. Therefore, the structural deformation, structural stress, anchor stress and contact surface contact state of the lock head all meet specification requirements under the design earthquake with good seismic capacity.