【作者】 叶锋；

【导师】 王民；

【作者基本信息】 西北农林科技大学 ， 水利水电工程， 2008， 硕士

【摘要】 砌石拱坝是在中小型水利工程中常见的坝体结构型式。它以水泥用量少,大量的砌石料、砂砾料可以就地取材,对施工机械和施工技术要求低,便于广大群众掌握等诸多优点而得到广泛的应用。因此,研究砌石拱坝的应力、应变对于坝体的设计、安全评价等均有重要的科学意义。本文在综合已有的研究成果上,利用大型商业有限元软件ANSYS对砌石拱坝在多种工况下坝体应力、应变进行了分析研究。在静力研究中考虑到了重力、水压力、温度、淤沙压力等荷载的作用,进行了坝体温度场分析,地震动力分析中详细研究了振型分解反应谱法,得到了坝体应力、应变一些规律,为坝体的设计和安全评价提供一些参考。本文通过计算分析主要得到如下一些结论:(1).本文通过坝体的温度场分析,可知温度对拱坝的位移影响较大,温降引起坝体向下游位移,温升引起坝体向上游位移;温度对应力的影响局限在较小范围内,对坝体拱端和表孔闸礅下部的应力有一定的影响。(2).本文用于求解砌石拱坝动水压力的方法和二次开发程序的模块,可以实现结构-水体的耦合分析,对砌石拱坝的动力计算结果符合一般规律。(3).静力分析结果表明,无论何种工况,坝体位移等值线基本对称;坝体拉应力较大值出现在闸墩与坝体交界处、两拱端上游面中部附近以及拱冠梁上游面底部附近,坝体压应力较大值出现在下游坝面拱冠梁中下部,对于有表孔的砌石拱坝,在坝踵、坝趾、闸墩等特征部位容易出现应力集中现象。(4).地震动力分析结果表明,不管是顺河流向还是垂直河流向,都将在拱坝的坝顶拱冠处产生较大的位移值,而坝体中下部出现的位移较小;坝体地震动应力的分布规律大致是坝体表面应力大,坝体内部应力小,下游侧的动应力较上游侧为大。在同一高程水平坝体截面上,坝体各点的水平地震动应力和地震剪应力呈由上游向下游逐渐增大的分布规律。更多还原

【Abstract】 The stone arch dam structure is the usual dam structure style in miniature water conservancy engineering.It can be made of a little cement,a mass of stone material,grit material can use local material,It requires low construct machine and technique,easy to be masteried by many people.So we must study the stress and deformation of stone arch dam,it’s very important to design and safety estimate.On the basis of the already research result,the stress and deformation of stone arch dam are analyzed using the commerce finite element software ANSYS in a variety of body condition, In static study,this analysis took into account the gravity, water pressure, temperature stress, soil and sand pressure,carry through heat-solid coupling effective. It traverses the vibration mode stack response spectrum in the earthquake dynamicl, finds some laws of the dam stress and strain, for the design and evaluation of the dam to provide reference information. The main conclusions are as follows by calculation:(1).In this paper, through the temperature field analysis of the dam, we can see that the temperature on the arch dam is a greater impact on displacement, the temperature drop downstream from the dam to the displacement, temperature rise caused the dam to the upper reaches of displacement, temperature stress on the impact limited to the lesser, The arch dam-and table-gate dun lower the stress does have a certain impact.(2).This paper used to solve the stone arch dam hydrodynamic pressure means and the secondary empolder of methods and procedures of the module, the structure can be achieved - the coupling of the solid-water body, the dynamometer result of stone arch dam results in line with general law.(3).Static analysis results show that no matter what conditions, the dam displacement contours basic symmetry;dam draw stress is bigger in the junction of the dam and frusta,upstream of the two arch extrenity and near the central beam crown. Near the bottom of the upstream face, body suppress stress is bigger in the lower reaches of the dam surface archbeam crown in the bottom of the hole for a table stone arch dam, the dam heel, toe dam, piers and other features of parts prone to stress concentration phenomenon. (4).Seismic analysis showed that, whether vertical or along the river,a greater displacement values will be in the top of the arch dam arch crown department, and the smaller displacement will be in the lower part of the dam;The dam seismic stress generally is that the body surface stress is bigger,the stress on the dam, the downstream side of the dynamic stress is bigger than the upstream side. Elevation at the same level of the dam section, the the level seismic stress and shock shear stress are gradually increasing from the upper to lower reaches of every points of dam.更多还原