Arc Method Of Improvement, Slope Stability Analysis

Circle slices method, with its simple principle and brief formula, is still popularly applied in assessment of earth slope stability. However, it exists two aspects of weakness in practical application. The first is difficult to search the most possible sliding surface ; the second is complicated to deal with slices. So the author proposed some compliments in circle slices method as follows:First, after definite integral method instead of the present slices method was suggested by Chen zuyu, a lot of experts studied at this aspect because this method can get rid of the slicing. The author also proposed the formula to calculating the factor of safety according the method is deduced. The integral method could get precise solution and simplify process of computing. Some cases are calculated to testify the exactitude of the method.Second, on the basis of a lot of present results, the author introduced a new method of searching the most possible sliding surface. It supposed that the circle of sliding surface run through the foot of slide. The factor of safety is transmitted to the function of x coordinate of the intersection point of the tangent at the scrap of the circle and x axis. So, the Two-dimension area of searching is changed to One-dimension. The searching area is a limit domain, therefore, the result of searching would be accurate.Third, in the loess area, there is tension fractures on the top of slope generally. Deep of the tension fracture could be deduced theoretically by Columb strength theory. The circle of sliding surface should develop from the end of fracture down, and the weight of soil above the level of the end of fracture could be considered as up load. Then the method according with this case is verified. Cases as examples are applied to check this method and the results are practical and feasible.At last, computing program on the method is provided with detail instruction.