Numerical Simulation On Deformation Test Of Layered Rock Mass

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.