【摘要】 强震区的杨房沟拱坝的抗震安全问题为众多研究者所关注。本文用拉格朗日不连续变形分析(LDDA)模拟拱坝横缝,采用黏弹性边界作为吸能边界来模拟无限地基辐射阻尼,建立了拱坝地震自由场输入模型,进行了杨房沟拱坝动力响应分析,对辐射阻尼和拱坝横缝对坝体应力的影响、拱坝横缝在地震作用下的张开情况以及坝体静动综合应力进行了分析,得出了如下结论,考虑坝体横缝张开和地基辐射阻尼效应影响后,杨房沟拱坝的地震动力响应明显降低,大坝横缝张开度最大为6mm,在横缝止水可允许的变形范围之内,在进一步优化大坝体型基础上,杨房沟拱坝在设计地震作用下的抗震安全是可以保证的。更多还原

【Abstract】 The seismic safety of Yangfanggou Arch Dam,located in the meizoseismal area,is concerned by many researchers.In this paper,The Lagrangian Discontinuous Deformation Analysis(LDDA) is implemented to model the movement of arch dam contraction joints.Viscoelastic boundary is used as energy absorbing boundary to simulate infinite foundation radiation damping,and the earthquake free field input model of arch dams is established.The dynamic response analysis of the Yangfanggou Arch Dam is performed,and then,the influence of the radiation damping and arch dam contraction joints on the stresses of arch dam,the open of contraction joints of arch dam under earthquake action,and the compound stress of static and dynamic on dam are deeply analyzed.Major results can be concluded as follows:dynamic responses of the Yangfanggou Arch Dam significantly decrease in the case of considering open joints and foundation radiation damping effects;dam contraction joints maximum opening is 6 mm,in the range of permissible deformation of joints sealing;on the basis of further optimization of the dam body,the Yangfanggou Arch Dam subjected to design earthquake seismic safety can be guaranteed.更多还原