| With the further economic growth, the construction of railway, highway and hydroelectric in our country is undergoing rapid growth. There are many artificial slopes, and many slope remediation problems appear. The technique of stabilizing piles with prestressed anchored cables is an effective measure in landslide remediation works, which nowadays has a wide application in many fields. However, studies on theory of these structures are delayed greatly than their applications. In this thesis, mechanism and stability of stabilizing piles with prestressed anchored cables are studied by theory study, numerical simulation and field test in Xujiadong landslide. Major research work is summarized as follows:(1) Through long term deformation monitoring of the landslide, the displacement information is analyzed and feed back in time. The influence factors of landslide deformation are researched and the deformation trend is predicted. It has been proved that the observed data can correctly reflect the deformation of the landslide and meet the requirement for the timely treatment of the dangerous. It ensures the safety in construction period and normal operation.(2) Based on experimental results obtained from pull-out test, the axial load distribution as well as shear stress distribution at the interface of anchoring section is studied.(3) Based on the results obtained from the in-site experimental study, factors that contribute to instantaneous loss of load are examined, and three parameters, namely load applied by the jack to the cables, free length, and anchored length, are recognized as the main factors. Then grey-correlation theory is applied to analyze the correlation between these parameters and instantaneous loss of load. It is shown that the load applied by the jack to the cable and the free length have more influence than anchored length.(4) Monitoring of the long-term behaviour for up 3 years of six prestressed grout cables indicates two distinct phrases: phase â… , lastingabout 6-15 days, throughout which the losses of load are rapid; and phase II, which is marked by a slower and uniform rate of load loss. A method of unequal interval gray forecast GM (1,1) model is presented to solve load loss after lock-off. The study shows that theory analysis is in good agreement with experimental results.(5 ) Based on the monitoring and tests of Xujiadong landslide, a three dimensional numerical model for the landslide is established. A three-dimensional finite difference method is adopted to analyze Xujiadong landslide during and after excavation. On the basis of calculation results obtained from simulation, by means of analysis of displacement value of characteristic points in the main section and displacement vector, deformation features, stress variety and the evaluation of the global stability of the slope.(6) A three dimensional numerical model for stabilizing piles with prestressed anchored cables is established. Piles interact with rock via shear and normal coupling springs. The shear behavior of the cable-rock interface is cohesive and frictional in nature. Moment distribution, stress of normal coupling springs of piles can be received by studying the model. Axial load distribution as well as shear stress distribution at the interface of anchoring section are simulated.(7) Based on the three-dimensional elasto-plastic shear strength reduction finite difference method* slope stability in different stages is evaluated by the global safety factor.(8) Slope stability analysis is performed by limit equilibrium methods and finite difference modeling, and results of the two methods are analyzed. It is indicated that shear strength reduction finite difference method is appropriate to stability analysis of slope.(9) Monte Carlo method is used to calculate the reliability of Xiujiadong landslide. A comprehensive study is conducted to assess how uncertainty in design parameters affects the probability index values.
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