【作者】 冷霜；

【导师】 喻勇；

【作者基本信息】 西南交通大学 ， 固体力学， 2008， 硕士

【摘要】 层状岩体是由多种不同属性、不同厚度岩层按某种方式组合而成的天然复杂岩体,其变形特性明显不同于单一岩体,故其变形参数就不单取决于某一层岩体的变形参数,而是与各岩层的厚度、岩层倾角、相互之间的组合方式等因素有关的。而工程中普遍采用承压板法变形试验来研究岩体的变形参数,存在的问题主要是这种方法的试验结果大都是复杂岩体的等效变形模量,不能够准确反映出各个岩层对试验结果的影响以及每个单层的变形参数。因此,正确分析层状岩体对承压板试验结果的影响具有十分重要的意义。本文以层状岩体为研究对象,主要开展了以下的研究工作:(1)对层状岩体进行合理概化,介绍了水平层状岩体在垂直方向荷载作用下,各层岩体位移与变形参数的理论解。(2)对现场承压板变形试验包括柔性承压板、刚性承压板以及中心孔试验的试验原理、试验方法与技术进行了较为系统的总结,并阐述了试验中存在的相关问题。(3)采用ANSYS有限元软件,对含有软弱夹层的倾斜层状岩体进行数值模拟,主要研究了软弱夹层与试验点间的距离和软弱夹层的倾角对层状岩体变形模量测试结果的影响,并得出了一些规律性的认识。(4)在软硬相间的层状岩体试验洞条件下,对承压板试验进行数值模拟,研究了软硬相间岩体的间距和倾角对承压板试验结果的影响。(4)结合ANSYS软件的优化功能和位移反分析的理论对水平和倾斜层状岩体各个岩层的变形模量进行了反演,并通过算例分析得出了较为合理的结果,说明利用ANSY优化程序反演层状岩体变形模量的方法是可行的,从而解决了承压板法变形试验只能测得岩体等效变形模量的缺点。更多还原

【Abstract】 Layered rock mass is natural complex rock mass with different attributes and thickness which were assembled in some way, so its characteristics are very different from the uniform rock. Its deformation parameters is not only decided by each layered rock mass deformation parameters, but also decided by the thickness of each rock layer, the rock layer inclination angle and combination way of layers. In engineering practices, bearing plate test is widely applied to study rock mass deformation parameters. However, this method has a main problem that the resulted deformation modulus is the equivalent modulus which can’t accurately reflect the influence of each rock layer to test result and each single layer’s deformation. Therefore, it is extremely vital significant to analyses the influence of layered rock mass on the bearing plate test.This paper takes layered rock mass as object of study, and the following major research work has been done:(1) Through the layered rock mass was carried on reasonably melts, displacement and deformation parameter of Level layered rock mass theory solution was introduced under vertical load.(2) The test principle, the method and technology of bearing plate tests containing flexible bearing plate test, rigid bearing plate test and plate test with a central hole had been systematically summarized.(3) Numerical simulations for incline layered rock masses were carried out by ANSYS software. The influences of distance from test point to the first layer and the inclination angle of layer on the deformation modulus of layered rock masses were studied. Some regular conclusions had been obtained.(4) For soft and hard alternating layered rock mass, numerical simulations of bearing plate test were carried out. The influences of the space between soft and hard rock mass and the inclination angle on the bearing plate test result were studied.(5) With optimization function of ANSYS software and theory of displacement back analysis, each rock layer’s deformation modulus of level and inclined layered rock mass were back analysed, and obtained a more reasonable result through the example analysis. It is shown that the method of using the ANSY optimization procedure to predict the deformation modulus of the layered rock mass is feasible. Thus the shortcoming of the bearing plate test which is only able to obtain the rock mass equivalent deformation modulus can be solved.更多还原