强震区高拱坝的两种抗震措施效果研究

Analysis of Two Kinds of Aseismic Measures for High Arch Dam in Meizoseismal Area

为研究拱坝在坝体上部跨横缝配筋和设置阻尼器两种抗震措施效果,以大岗山拱坝为例,基于在有限元软件ABAQUS平台上二次开发的有限元模型分析,采用限制缝面切向滑移的接触单元模型模拟切向完全约束的高拱坝横缝在地震动荷载作用下张开、闭合的非线性力学行为,并采用点点接触的弹簧单元模型表示横缝插筋的作用,应用ABAQUS中的阻尼器模型考虑设置阻尼器的作用。计算结果表明,两种措施均可控制强震区高拱坝在强震作用下横缝开度,但设置粘滞阻尼器后抗震作用不明显。

Two kinds of aseismic measures, collocating steel bars across the transverse joints and installing dampers at transverse joints on the upper of arch dam, are studied based on the finite element model of arch dam developed by the ABAQUS software. The type of contact elements which limit the joint surface slip in the tangential direction are used to simulate the nonlinear mechanical behaviors, i.e. open and dose, of the transverse joints constrained fully in tangential direction under dynamic load response. The point to point contact spring element is applied to express the steel bar across transverse joints. A damper model is used to simulate the damper located in the transverse joints. Two kinds of the seismic reinforcements have been proposed to reduce the maximum dynamic openings of transverse joints. However, the seismic effect of the damper located in the transverse joints is insignificant.