The Study On The Stability And Treatment Scheme Of The Swelling Rock Slope

Swelling rock is a special type of soft rock. It has the characters of rock and soil, but it is not ordinary rock or soil. Because it contains a large number of hydrophilic minerals, it is very close to the water, and it has strong hydrophilic characters. At the same time, when the humidity changes, the volume of it also changes greatly, which can cause a greater internal stress while its deformation is bound. Due to the complexity of the engineering properties of swelling rock, it results in a variety of serious and widely distributed geological disasters, which causes the problem of swelling rock to be one of the most concerned problems in engineering field. With the rapid development of China’s economy, more and more construction projects are built through the areas of swelling rock inevitably, and its disaster prevention issues have become increasingly prominent.In water conservancy project, the drainage slope treatment of swelling rock has been the most problem in the engineering field. What’s more, compared to the swelling rock channel slopes to deal with the expansion of the road, rail and other geotechnical cutting slopes, the treatment of water channel slopes are adjacent to water, which deepens the difficulty of ways to deal with swelling rock, as well as it has special character of the presence of permanent cross section. Form an instability channel project, this essay summarizes and absorbs the results of previous studies to mainly study the engineering properties of swelling rock, the reasons and preventions of the instability of swelling rock channel slopes, by means of spot investigation, testing, theoretical analysis and numerical calculation and so on.In the paper, by researching on the instability of swelling rock channel slopes in the field, and understand comprehensively the field characters, the engineering geological conditions and hydro-climatic conditions of swelling rock. Through a series of indoor and outdoor tests, swelling rock mineral composition, structural features, physical and mechanical properties, fracture, expansion and contraction properties and strength properties were studied. According to these test results obtained, the limit equilibrium method and finite element combining swelling rock channel slope instability were used for further research to identify the exact cause of instability. According to the reason of the instability of channel slope, replacement method and drainage method both were used to deal with the instability of channel slope. In order to ensure the stability of the instability of swelling rock channel slopes processed, using strong drainage wells as complementary programs.Author summaries the results of indoor test and the reason of the instability, can get conclusions:Author found crack is very complex after observing the situation of excavation:There are micro-cracks and growth of cracks; surface distribution of cracks and shallow and deep cracks; both the random distribution of non-directional cracks, there are combinations and the dominant direction of cracks. Because of the existence of these cracks the soil into the discontinuity, these cracks break the homogeneity and structural of the soil, cause the soil that have the weak structural plane, provide access for water infiltration, reduce soil strength, the presence of weak structural plane, when the water into the easy to form a weak zone caused by the channel slope instability.Moisture content, overburden pressure and the degree of compaction of swelling rock affect the expansion and shrinkage of the swelling rock. Expansion is proportional to the degree of compaction, is inversely proportional to the moisture content; shrinkage and degree of compaction is inversely proportional to the same proportional to the moisture content. In this paper, swelling rock that the expansive force is large, the diversification of moisture content cause the soil within a certain depth of the channel slope to non-uniform expansion and deformation, at the same time, expansive force is released, change the stress state of channel slope. Because the stress concentrate in the foot of the slope, lead to the shear stress of the soil at the foot of the slope will first cross the peak intensity and destruction, the shear stress of pre-destruction zone reduce uninstall and release the strain energy, cause the shear stress of the soil at the adjacent area will cross the peak intensity, the destruction zone is gradually expanding, when the equivalent plastic strain to a range of the slope from the foot of the slope completely through the channel slope to produce instability slide.The strength of Swelling rock is concerned with the material composition of rocks,the change of surrounding environment moisture (wet and dry cycle), The compaction rate and initial moisture content of soil, overburden pressure, development of the fissures and the suction of expansive soil and other factors.The research results of this article have got good application in the actual construction, and have made considerable economic and social benefits.