基于广义附加质量法的坝—库系统动力分析  

Dynamic Analysis of Dam-Reservoir System Based on Generalized Added Mass Method

作　　者：徐江通 陈江[1] 熊峰[1] XU Jiang-tong;CHEN Jiang;XIONG Feng(College of Architecture and Environment,Sichuan University,Chengdu 610065,China)

机构地区：[1]四川大学建筑与环境学院,四川成都610065

出　　处：《水电能源科学》2024年第11期92-94,144,共4页Water Resources and Power

摘　　要：鉴于广义附加质量法仍是目前坝工抗震分析的主要计算方法,介绍了坝—库系统动力响应分析的广义附加质量法及其在ANSYS中的实现步骤,并以某高拱坝为算例,比较了广义附加质量法与考虑库水压缩性的流固耦合法的计算结果。结果表明,两种方法所得自振频率基本一致。在阻尼比相同的情况下,广义附加质量法所得动力反应明显大于流固耦合法,其原因在于一方面广义附加质量法基于坝体刚性假定,而弹性坝体沿坝高具有加速度放大作用;另一方面广义附加质量法额外计入了节点切向惯性力,导致外荷载增加。通过适当增加广义附加质量法中的阻尼比,可使其动力反应计算结果的量级与流固耦合法基本一致。In view of the generalized additional mass method is still the main calculation method for seismic analysis of dam construction,this article investigates the dynamic response analysis of dam-reservoir systems based on the general-ized added mass method,and outlines its implementation steps in ANSYS.Taking a high arch dam as a case study,the results of the generalized added mass method is compared with those of the fluid-solid coupling method with consideration of reservoir water compressibility.The results indicate that the natural vibration frequencies obtained by both methods are generally consistent.Under the same damping ratio,the dynamic response by the generalized added mass method is sig-nificantly larger than that of the fluid-solid coupling method.The reasons are as follows:The former is based on the rigid dam body assumption,while the elastic dam body has acceleration magnified effect along its height.The generalized add-ed mass method additionally considers the tangential inertial forces at the nodes,leading to increased external loads.By suitably increasing the damping ratio in the generalized added mass method,the magnitude of its dynamic response results can align more closely with those of fluid-solid coupling method.

关 键 词：混凝土坝 地震反应 广义附加质量法 流固耦合 阻尼比 

分 类 号：TV312[水利工程—水工结构工程]