Swelling Rock' Experimental Study To The Project Feature And Exploration To Machanism For New Yun-Gui Railwat Baise Basin

Swelling rock has a feature of swelling, softness and disintegration when it absorbs water; however, it will shrink and rend when swelling rock is dehudrated, which has been a difficulty in application for long time. This essay mainly aims at the swelling rock in Yun-Gui railway Baise basin and a research of the feature of the swelling rock project and exploration to mechanism of disease is given by author. Main contents are as below:1 .Through the survey of geology, the author understands the topography, distribution and engineering geology, at the same time, a research about swell-shrink, fragmentation and low intensity of the swelling rock is performed2. A research to the composition and microscopic structure of the swelling rock is carried out by technology which includes particle composition, chemical composition, X-ray powder diffraction (XRD) and scanning Electron Microscope (SEM).3 .According to shear strength test and unconfined compression strength test, shear strength and unconf ned compression strength of the swelling rock are gained. This essay also analyse the influence of shear strength and tension strength which is caused by moisture content of initial swelling and weathering of swelling rock. There is a duadratic curves diminishing relationship about expansion rock cohesion between swelling rock's initial moisture content and tension strength, A logarithmic reduce relationship is stated with the increasing of swelling rock's initial moisture content, namely, the swelling rock's initial moisture content and cohesion's logarithm decreases with a linear decreases relation, angle of internal friction increases with the moisture content of initial swelling. With the expansion of rock weathering intensity increases, shear strength of rock and compressive strength will decreases.4. According to water-physical properties test of the swelling rock, index of swelling pressure and swelling ration, etc. is gained. This essay focuses on an analysis of the influence of the swelling rock which caused by water and it also corrects the swelling rock stress-strain constitutive relationship that was put forward by Huder-Amberg. The author designs the new test of swelling deformation test in order to analyse the swelling deformational influence of the swelling rock caused by water. Based on test results, the author divides the rock deformation into 6 deformation stages and sets a concept of "the water content of initial swelling".5. This essay analyses the swelling rock project disease mechanisms, especially the swelling rock slope disease mechanisms. A suggestion of governance the swelling rock project disease is raised6. Combined with the practical example of this project, the author analyses the intensity of swelling rock values. These aspects should be taken into consideration, such as design conditions, the construction condition, operating conditions, strength attenuation and so on, especially the fact that the rock strength will decrease with time goes by should be taken into consideration and choose design index reasonably. A new thought which is about slope treatment is raised, through establishing deformation layer, the problems of swelling deformation and swelling pressure can be resolved; parameter designing is based on the weathering features of slope.