Stability Analysis Of Slope Based On Improved Imbalance Thrust Force Method And The Realization Of Its Program

The reliability analysis of slope is a key problem in engineering. In traditional stability analysis, the limit equilibrium method is the most wide applied method in slope stability analysis. Simplified arithmetic such as imbalance thrust force method has a wide application in water conservancy and railway sector because of some advantages such as simple, applicable and convenience. However, the calculating precision of imbalance thrust force method is needed to discuss. In addition, groundwater, surface loading and seismic force are the basic inducements of coast occurring and factors that doesn't allow ignoring. In stability analysis, considering the uncertain factors of slope material and studying the reliability analysis based on stability analysis of slope has great applied significance and practical value.Sometimes, there is no explicit expression in slope reliability calculation. Aiming at resolving the problem, a new response surface method is formed by combining classical response surface method with the stability analysis method.In this paper, it introduces the keystone of stability analysis and reliability analysis. Through the deeply study of the inherent limitation of imbalance thrust force method and the influence of each factor, establishes a new improved method, changing grade symmetrically at midpoint method. And then taking the groundwater, surface loading, seismic force, anchoring force and reinforce into account, based new slope stability analysis model. Next, for the complex instance that there is no explicit expression in slope reliability calculation, taking the Morgenstern-Price method or before and after improved imbalance thrust force method as simulated technique, a new response surface method based on Morgenstern-Price method or before and after improved imbalance thrust force method was established.Based on these theories, a program using Visual Basic language has been unceasingly developed and it can run in Windows environment. The program can calculate reliability index in multilayer slope and any configuration slip surface of slope. It has much using flexibility in scope and has no limit in distributing and correlation of random variables. Combined the stability analysis with the reliability analysis, it consists of five parts, such as data processing and distribution hypothesis test, imbalance thrust force method improving, slope anchoring and reinforcing, slope reliability model inputting, reliability index calculation and sensitivity analysis. Then the program is used to calculate some examples. The results indicate that the improved method and the program are utility and effective. And using the program to discussing about the influence of the variability of random variables in reliability index of multilayer slope, the results indicate that the changing tendency of reliability index is consistent with that of isotropic slope. However, the influence of the variability of random in reliability index not only relates to average value but also to the layer in which the variability of random locate. So the influence of the different random variables of different soil layers should cause our recognition in the engineering.