【作者】 赵锦华；

【导师】 陈健云； 朱彤；

【作者基本信息】 大连理工大学 ， 防灾减灾工程及防护工程， 2007， 硕士

【摘要】 随着国民经济的发展，为满足对绿色能源越来越大的需求，在“西部大开发”和“西电东送”战略任务支撑下，在本世纪上半叶，我国水电能源的开发利用将进入重要的发展时期。按照国家对能源和水利事业的发展规划，一大批坝高在100～300m左右的世界级高混凝土坝即将在我国西南地区开工建设。这些大坝多建于高烈度地震区，坝址地质条件复杂，设计地震加速度高。目前，人们对强烈地震作用下混凝土高坝的非线性动力反应、破坏过程、破坏机理和可能的破坏形式还知之甚少。因此，结构动力模型试验与数值分析成为了解混凝土高坝非线性动力响应与地震破坏形态的重要手段。本文将针对模型试验中理想的混凝土仿真材料的力学性能和本构模型进行深入研究，同时，利用得到的仿真材料非线性本构进行重力坝模型动力特性数值分析。主要做了以下的工作：1．为了得到模型试验所需要的理想仿真混凝土材料，在电子材料试验机上对大连理工大学研制出的仿真混凝土材料的力学性能和各种参数进行了较详细的研究。对仿真混凝土进行了单向应力状态下的拉、压试验，系统地研究了龄期、配比、养护温度等对仿真混凝土强度及变形特性的影响。结合原型混凝土的力学特性，研究了仿真混凝土的拉、压应力一应变曲线规律，并确定其相应的本构模型。2．进行了仿真混凝土的抗剪试验、断裂破坏试验，测试了仿真混凝土材料的抗剪强度及断裂韧度并得出其变化规律。并研究了应变速率对仿真混凝土抗拉、抗压性能的影响，探讨了动荷载下仿真混凝土的破坏机理。3．数值分析：采用仿真材料的非线性本构，在静力条件下，对龙开口重力坝坝段进行非线性静力分析，得出其在空库工况下和满库工况下的位移和应力的分布规律。在动力荷载作用下，通过输入规范谱地震波，进行动力时程分析得出其在地震荷载作用下坝体的抗震特性，并得出其动态条件下坝体的抗震薄弱部位。本文紧密联系实际工程，其研究成果对设计类似工程具有较大的参考和借鉴价值。本文最后对所做工作进行了总结，并提出进一步工作的发展方向和前景。更多还原

【Abstract】 With the development of the national economy,especially supported by the policy of the Great Development of the West and the Power Transmission from West to East,exploitation and utilization of water power has stepped into the key development stage during the first half of present century.A batch of dams which are 100-300 metres concrete dams in the world have being constructed in southwestern China. These high dams lie in the High-intensity Earthquake Area,where geological condition is very complex and earthquake acceleration is high.At present,there is little knowledge for people about nonlinear dynamic response,damage process,damage mechanism and probable failure modes for high concrete dams which are in the high-intensity earthquake.Therefore, the dynamic structural model test and numerical analysis are important means to know nonlinear dynamic response and probable failure modes for high concrete dams.This paper makes deeper research for mechanical property and constitutive model of emulation concrete in model tests. Meanwbile,numerical analysis for emulation concrete dynamic character which is using of constitutive models in model dam test is employed.The main works of this paper are as follows:1.The mechanical property and various parameters of emulation concrete are analysised in order to gain our ideal emulation concrete.The uni-axial compressive and tensile tests are performed on the SANS electrofluid machine.On the basis of experiments,the relationship in curing time, mix ratio,curing temperature, strength and deformation characteristics are studied systematically and completely.At the same time,tensive & compressive constitutive model of emulation concrete are established based on normal concrete’s.2.The direct shear tests and three-point beam tests are employed to measure the shear strength and fracture toughness and study their corresponding variation law.And research on strain rates effect on tensive and compressive constitutive,especially damage mechanism of emulation concete in dynamic load.3.Numerical Analysis: Static analysis is used in both empty reservoir and full reservoir situation in nonlinear constitutive model of emulation concrete,in order to get the distributing of the stress and the displacement. At last, based on the numerical analysis is carried out to calculate the displacement and stress under the earthquake load and research the dam’s dynamic crack and weak sections. All of work of this paper is combined with the practical project and the research conclusions provide the practical reference to the design of similar projects. At last,after drawing the conclusion of the work of the paper,the expectation of advanced research is put forward.更多还原