桩—土—渡槽结构相互作用的拟动力试验及计算研究

发布时间：2018-03-28 01:33

本文选题：渡槽　切入点：抗震　出处：《湖南大学》2014年博士论文

【摘要】：在20世纪末，兴建跨流域调水工程已成为解决我国水资源分布不均匀问题的重要手段，对我国国民经济的发展有着重要意义。随着我国南水北调工程的开工建设，大流量、大跨度渡槽结构不断涌现。大型渡槽结构的抗震问题已成为工程抗震领域研究热点之一。大型渡槽结构抗震计算方法的研究有着重要的意义，不仅能满足南水北调工程中大型渡槽结构抗震设计的需要，也能为建立渡槽结构抗震设计理论和方法提供参考资料。本文主要对渡槽结构横槽向地震响应规律、渡槽结构横槽向抗震计算模型、槽墩高度对渡槽结构横槽向动力特性及横槽向地震响应的影响规律进行了研究。本文的主要研究工作及成果如下： (1)开展了渡槽结构原理性的多自由度子结构拟动力模型试验。通过渡槽结构拟动力模型试验对土-桩-渡槽结构-水体动力相互作用体系的横槽向地震响应规律进行了研究，试验结果表明：在输入地震波峰值加速度相同时，渡槽结构在不同试验地震波作用下的横槽向地震响应峰值存在较大差异；槽内水体与渡槽结构的流-固耦合动力相互作用可能减小也可能增大渡槽结构横槽向地震响应峰值，其影响规律主要与水体对渡槽结构调频作用大小和水体动水压力两种因素有关；随着输入地震波峰值加速度的增大，底部桩周附近土体塑性发展使得试验模型的刚度等特性发生变化，从而使得渡槽结构横槽向地震响应时程曲线波形及其峰值大小表现出明显差别。 (2)建立了拟动力试验模型的整体有限元仿真计算模型，对拟动力试验模型横槽向地震响应进行了仿真计算，并与试验结果进行了比较，结果表明本文建立的拟动力试验模型整体有限元仿真计算模型能够估算拟动力试验模型的横槽向地震响应，并能够较好地反映槽内水体对试验模型横槽向地震响应的影响。同时，本文另外建立了两种试验模型的整体有限元计算模型，分别对拟动力模型试验中所没有考虑的土层运动和土体的计算范围取值大小对渡槽结构横槽向地震响应的影响进行研究，结果表明：采用拟动力试验方法能够较好地得到渡槽结构横槽向地震响应规律，获得的渡槽结构横槽向地震响应峰值误差比较小。 (3)建立了拟动力试验模型简化有限元仿真计算模型，对渡槽结构横槽向地震响应进行了仿真计算，并与试验结果进行了比较，结果表明本文建立的简化有限元仿真计算模型能够近似地估算试验模型的横槽向地震响应，并能够较好地反映槽内水体对试验模型横槽向地震响应的影响。同时，通过对简化有限元仿真计算模型地震自由场输入和地震惯性力输入计算结果的比较可知：两者的横槽向地震响应峰值大小有一些差别，但仍能够较好地反映试验模型横槽向地震响应规律。另外，通过对简化有限元仿真计算模型地震自由场输入计算结果与拟动力试验模型整体有限元模型三计算结果的比较可知：两者得到的渡槽结构横槽向地震响应在波形、峰值大小及其频谱特性上有一定差别，但两者反映的渡槽结构横槽向地震响应规律是一致的。 (4)以Housner弹簧-质量简化模型及土-桩非线性动力Winkler地基梁简化模型为基础，建立了一种可以同时考虑流-固耦合动力相互作用与土-桩非线性动力相互作用的渡槽结构横槽向抗震简化计算模型，对拟动力试验模型横槽向地震响应进行了仿真计算，结果表明该模型能够近似地估算试验模型的横槽向地震响应，并能够较好地反映槽内水体对试验模型横槽向地震响应的影响。同时，通过对自由场输入和地震惯性力输入计算结果的比较可知：两者的横槽向地震响应峰值大小有一些差别，，但仍能够较好地反映试验模型横槽向地震响应规律。另外，通过对该模型与整体有限元模型三计算结果的比较可知：两者得到的渡槽结构横槽向地震响应在波形、峰值大小及其频谱特性上有一定差别，但两者反映的渡槽结构横槽向地震响应规律是一致的。 (5)在假定槽墩截面和其他参数基本不变条件下，应用本文建立的渡槽结构整体有限元计算模型、渡槽结构简化有限元计算模型和渡槽结构横槽向抗震简化计算模型三种计算模型，开展了槽墩高度对矩形渡槽结构横槽向动力特性及横槽向地震响应影响规律的计算分析研究。结果表明：随着槽墩高度的增加，渡槽结构横槽向振动基频呈现明显减小趋势，渡槽结构关键部位的动力响应峰值等也存在递减趋势。最后，讨论了今后将进一步深入研究的问题。
[Abstract]:At the end of twentieth Century, the construction of inter basin water transfer project has become an important means to solve China's uneven distribution of water resources problem, is of great significance to the development of our national economy. As China's water diversion project construction, large flow, large span aqueduct structure emerge. Seismic problem of large aqueduct structures has become a hot research topic in seismic field engineering.
The research on the seismic calculation method of large aqueduct structure is of great significance. It not only meets the needs of seismic design of large aqueduct structure in the south to North Water Diversion Project, but also provides reference for establishing the theory and method of aqueduct structure's aseismic design.
In this paper, the response law of transverse groove to aqueduct structure, aqueduct structure transverse groove seismic calculation model, the influence of pier height on transverse groove dynamic characteristics and transverse groove seismic response of aqueduct structure are studied.
(1) to carry out the multi degree of freedom structure principle of aqueduct structure of pseudo dynamic model test. The aqueduct structure pseudo dynamic model test of soil - pile - aqueduct structure water interaction system of the cross slot to seismic response are studied. The experiment results show that the peak acceleration of input seismic waves at the same the transverse groove of aqueduct structure under different seismic waves under test to the seismic response of different peak; tank water and aqueduct fluid solid coupling interaction may decrease also may increase the aqueduct transverse trough to peak seismic response, the effect of the main water to aqueduct structure and hydrodynamic size and frequency modulation effect the pressure of two factors; with the increase of the peak acceleration of input seismic wave, the bottom of the pile near the soil plastic development makes the stiffness characteristics of the test model change, thus The transverse trough of the aqueduct structure shows obvious difference to the waveform of the seismic response time curve and its peak value.
(2) calculation model of finite element simulation of pseudo dynamic test model, the pseudo dynamic test model of cross slot to seismic response is simulated, and the results are compared with the test results, the results show that the pseudo dynamic test model finite element simulation model to estimate the earthquake response of transverse trough pseudo dynamic test the model, which can reflect the influence of the water tank test model of cross slot to seismic response. At the same time, this paper also established the finite element model of two kinds of test model are studied respectively, the influence on the calculation does not consider the scope of the proposed dynamic model tests of soil and soil movement the value of aqueduct transverse groove to the seismic response results show that the pseudo dynamic test method can effectively get the aqueduct cross slot to obtain the seismic response of aqueduct, node The peak error of seismic response to seismic response is relatively small.
(3) the establishment of the pseudo dynamic test model simplified finite element model, the calculation of the aqueduct structure transverse groove to the seismic response is simulated, and the results are compared with the test results, the results show that the simplified finite element simulation this paper established the calculation model is used to test cross slot experimental model to the earthquake response approximation, and can reflect on the water tank test model of cross slot to seismic response. At the same time, based on the simplified finite element simulation model of earthquake free field input and input seismic inertia force comparison results: transverse groove both to the seismic response of some of the difference in peak size, but still be able to reflect the test cross model in response to the earthquake of groove. In addition, the calculation model of seismic free field of simplified finite element simulation input calculation results and pseudo dynamic test model of finite element model of the whole three computing nodes The comparison of the results shows that there is a certain difference in the wave shape, the peak value and the spectral characteristics of the aqueduct transverse slot to the seismic response obtained from both of them, but both of them reflect the law of the transverse groove to the seismic response of the aqueduct structure.
(4) Housner mass spring simplified model and nonlinear soil pile dynamic Winkler foundation beam model as the foundation, established a considering aqueduct transverse groove fluid solid coupling dynamic interaction and nonlinear soil pile dynamic interaction to seismic simplified calculation model, the pseudo dynamic test model of cross groove to the seismic response were simulated. The results show that the model can approximate horizontal trough test model to estimate the seismic response, and can reflect the influence of the water tank test model of cross slot to seismic response. At the same time, by comparing the input of the free field input and seismic inertial force calculation results: cross the seismic response to the trough there are some differences between the magnitude of the peak, but still be able to reflect the test model to the earthquake response of transverse slot. In addition, based on the model and finite element model of the whole calculation three The comparison of the results shows that there is a certain difference in the wave shape, the peak value and the frequency spectrum characteristics of the transverse groove to the seismic response of the aqueducts, but both of them reflect the seismic response law of the aqueduct structure transverse groove.
(5) under the assumption that the pier section and other parameters unchanged under the condition of finite element, the overall application of aqueduct structure calculation model of aqueduct structure simplified finite element model and the aqueduct cross slot to seismic simplified calculation model of three models, the pier height of the rectangular aqueduct transverse groove to dynamic characteristics and cross slot to seismic response research. Influence analysis law the results show that: with the increase of the height of the pier, the aqueduct structure transverse groove to the fundamental vibration frequency showed a decreasing trend, the key parts of the aqueduct structure dynamic response peak value also showed a decreasing trend.
Finally, the problems that will be further studied in the future are discussed.

【学位授予单位】：湖南大学
【学位级别】：博士
【学位授予年份】：2014
【分类号】：TV672.3

【参考文献】