Study On The Post Evaluation Of The Effectiveness Of Landslide Control

In this dissertation, combining the traditional geological survey theory, structure design theory with the modern Systematic Theory, Grey Theory and the Fuzzy Theory, the post evaluating principle and criterion of the effectiveness of landslide control are put up firstly. Furthermore, on the basis of analyzing a great deal of controlled landslides, how to evaluate the cognitive degree of character of landslide, how to determine the strength characteristic of landslide slip and how to determine the landslide thrust are discussed; Moreover, types and applicability of landslide control, and the designing methods of anti-sliding engineering are probed, and the optimum design of anti-slide pile are set forth. Then series post evaluation methods are presented, such as the check method of the landslide thrust, etc.Secondly, several large and complex landslides, such as K2730 I~# landslide of Elangshan along Chuanzang highway are surveyed; And the soil-stress box, reinforcing steel bar meter are buried in the retaining wall, anti-slide pill, and beam with pre-stress cable; And the displacement of anti-slide pile top, and ground displacement are monitored for a long time. Then, a new evaluating criterion of the effectiveness of landslide control, which is the ratio of in-situ thrust to the design-thrust (n=T/E_T), is put up primarily. In the same time, a Grey Model GM (1,1) of predicting displacement of pile top is set up. Furthermore, using the critical velocity of pile top's displacement, which is presented in the paper, the time when the anti-sliding pile becomes stable is attempted to forecast.Thirdly, using the Contact FEM source program completed by the authors, numerical calculation of the effectiveness of anti-sliding piles with different factors of landslide itself and different of controlling engineering structure, is analyzed respectively. And the optimum pre-stress of anti-sliding piles with cables, concerning the pile' end is fixed and without anti-force before pile, is put up.Finally, on the basis of above research, according to the engineering scale, construction process, the degree of using anti-slide ability in geo-body, the changing character of slip, etc., the eleven evaluating factors are chosen. In addition, using the Forced Decision of Systematic Theory, the method of determining weigh of evaluating factors is put forward. Then, using the Fuzzy Theory, a comprehensive evaluation model of the post evaluation is set up for the first time, which lays a foundation for establishing the criterion of landslide control.