超载频度对大坝稳定模型试验结果的影响研究及工程应用  

Influence Research and Engineering Applications of Overload Frequency on Dam Stability Model Tests Results

作　　者：朱自强[1,2] 祁玲 杨宝全[2] 陈媛 张林[2] ZHU Ziqiang;QI Ling;YANG Baoquan;CHEN Yuan;ZHANG Lin(Sichuan Water Conservancy Vocational College,Chengdu 611231,China;School of Water Resources&Hydropower,State Key Lab.of Hydraulics and Mountain River Eng.,Sichuan Univ.,Chengdu 610065,China)

机构地区：[1]四川水利职业技术学院,四川成都611231 [2]四川大学水利水电学院水力学与山区河流开发保护国家重点实验室,四川成都610065

出　　处：《工程科学与技术》2020年第2期95-102,共8页Advanced Engineering Sciences

基　　金：国家自然科学基金项目(51379139);国家自然科学基金项目(51609163)。

摘　　要：地质力学模型试验是研究大坝稳定安全的重要手段之一,其通过选择一定的超载频度进行逐级超载,获得模型大坝的变位、应变、破坏过程和破坏形态等结果,从而综合评价原型大坝工程的稳定安全性。因此,超载频度的选择直接影响试验结果的可靠性,需要进行深入研究。针对超载频度对模型试验成果的影响程度及超载频度的合理取值等问题,开展了不同超载频度(ΔP=0.2P、0.5P、1.0P)的地质力学模型试验,研究超载频度对大坝稳定地质力学模型试验结果的影响。结合数值计算和刚体极限平衡法的结果,确定了超载频度的合理取值,即ΔP=0.2P。在此基础上,将研究结果运用到丹巴水电站典型坝段坝基稳定分析中,通过模型试验获得了坝与地基的变位分布特征、变位关系曲线规律、破坏过程及破坏形态,提出了丹巴水电站典型坝段超载稳定安全系数,评价了丹巴水电站典型坝段的坝基稳定性和安全性,研究结果为大坝稳定地质力学模型试验的加载方式提供科学依据。Geomechanical model test is one of the important methods to study the stability and safety of dams.It selects a certain overload frequency to carry out step-by-step overloading test to obtain the results of displacement,strain,failure process and failure mode of the model dam,and to evaluate the stability and safety of the prototype dam project.Therefore,the choice of overload frequency directly affects the reliability of the test results and requires in-depth research.Aims at the impact of overload frequency on model test results and the selection of reasonable overload frequency,the geomechanical model tests with different overload frequencies(ΔP=0.2P,0.5P,1.0P)are carried out.The influence of overload frequency on the results of geomechanical model test is analyzed.Combined with the numerical calculation and the results of the rigid body limit equilibrium method,the reasonable value of the overload frequency is comprehensively analyzed and determined,that is,ΔP=0.2P.On this basis,the research results are applied to the stability study of the typical dam section of Danba hydropower station,and the geomechanical model test is carried out.Through the test,the displacement distribution characteristics and displacement curve,failure process and failure mode and overload stability safety coefficient of the dam and dam foundation of Danba hydropower station are obtained.The stability of the dam foundation of the typical dam section of Danba hydropower station is evaluated.The research results provide a scientific basis for the loading method of the dam stability geomechanical model test and help to improve the reliability of the test results.

关 键 词：大坝稳定 地质力学模型试验 超载频度 影响程度 合理取值 工程应用 

分 类 号：O319.56[理学—一般力学与力学基础]