Abstract:

The Wenchuan Ms 8.0 earthquake happened on May 12, 2008, resulted in tens of thousands of geo-hazards, such as collapse, landslide, debris flow, and brought a great threat to the safety of human life and property. After the Wenchuan earthquake, the Chinese government has carried out geohazard control project in the disaster area, adopting the construction of water drain, retaining wall, slope anti-slide pile, load shedding and toe back pressure. Although the geohazard prevention project has achieved good control effect in general, there are still some problems in the geohazard prevention and control project in the earthquake region. Through field investigation, based on analyzing the present technique and evaluation methods related to geohazards, an evaluation system for geohazard prevention and control projects has been established for the earthquake disturbed zone. According to the evaluation system, it is believed that the prevention effect evaluation system should include 3 first-level evaluation factors and 12 second-level ones. A comprehensive evaluation model was established for the effect of the prevention and control projects based on the AHP (analytic hierarchy process) method. It divided the prevention and control efficiency (R) into 4 grades: best (R≥0.85), good (0.70≤R<0.85), common (0.6≤R<0.70) and bad (too conservative or failure, R<0.6). On this basis, a comprehensive evaluation was made on Weiba landslide control effect, Pingwu County, and the result show that the control effect is common, which is consistent with the actual situation.

Key words: Wenchuan earthquake, earthquake disturbed region, geodisaster prevention and control project, evaluation index system, Weiba landslide