Study On The Deformation And Stability Of Cut Cliff Debris And Residual Soil Slopes

The slope project is one of the three big problems of geotechnical engineering; Cut soil slope is one of the important types of slope projects; Engineering construction of the traffic, such as highway, railway in the mountain area and hills area etc. is developing rapidly, which will inevitably encounter the deformation and stability of cutting cliff debris and residual soil slopes. And this will be one of the important technological problems to be solved in a quite long time at present and even in the future. Combining with the research task Researching on the deformation and stability of deep excavated cuts and high filled embankment of the Traffic Department in Fujian Province, based on the residual soil slope project on the project site at K15 +183 of Yong- Zhang highway (Yong'an section), adopting non-linear theory, modern monitoring technology and numerical simulation technology, the deformation and stability of cutting cliff debris and residual soil slopes have been studied systemically and synthetically in the thesis. At the same time theory analysis, the analysis and estimate of field monitoring are taken into account in this course. Main research work and working achievement are summed up as follows:(1)With the acquaintance of the trends and development about the deformation and stability of slopes at home and abroad, slopes are classified and summarized systemically. In order to offer the guidance to the deformation and stability of cut slopes, the geological mode and the mode of failure of cut slopes have been analysed, considering the influence of the deformation and stability of soil slopes. (2)By building geological models and mathe-mechanical models, this context has created a clear valuation approach in research, It concluded the deformation and stability of cutting cliff debris and residual soil slopes. Using the balanced method of the utmost limits analytic method (analytic method and simplified Bishop method) and numerical analysis method (non-linear finite element Ansys). And combining with compound analysis, this thesis has calculated and estimated the deformation and stability of slopes of the cliff debris and residual soil slope project on the project site at K15 +183 of Yong'an section of Yong- Zhang highway; (3)In the course of the cut slope excavation Inner displacement has been in control of real time field monitoring. It has analysed the development of inner soil mass displacement, and also analysed the ruleof development of displacement of inner soil body of the slope. (4)Based on current research fruits, corresponding calculated procedure was programmed, which was calculated, analysed and compared. Its validity and applicability is validated by the different displacements of the slope of the project site at K15 +183 of Yong'an section of Yong-Zhang highway. (5)By the simulation and analysis of large-scale non-linear finite element soft Ansys, Not only the real tine stress- strain relation with each excavation time step is analysed, but also corresponding with the routes of the actual clinometers are simulated. The result is similar to the facts, which is approved by the simulated calculation and analysis to the each excavation time step. (6)It also uses synthetically monitoring method and utmost limits analytic theory. Through the optimized calculation and analysis of primary designed rate of slope and geometry shape at K15 +183 of Yong'an section of Yong- Zhang highway, the satisfactory achievement is obtained.The calculating and analysis results are shown as follows:1.The cut slope natural stability is higher and its stability safety factor is 1.47~1.592.The maximum lateral displacement is 4.70 cm (NLFEP)~5.38 cm (Ansys) after the excavation of the slope, it's more close with actual values, at the same time the resilience phenomenon will appear at the top of slope in the later excavation of the slope3.The number value results indicate: with the excavation step number increasing, the major and minor principal stress values of the slope are adjusted constantly,...