Discussion Of The Safety Assessment Technique Of Gravity Retaining Structure

Gravity retaining structure is a building using its own gravity to prevent the filling behind the structure collapsing and to maintain its stability, which is widely used as a traditional structure in railway and highway roadbed slope supporting projects, also widely used in bridge engineering, water conservancy engineering.With the speed of the domestic every railway continuously increasing, the axle load increasing and the stress increasing, the force and deformation of the existing gravity retaining structure also will change. At the same time, the work environment and conditions of the existing gravity retaining structure is also will change after a period of operation. In such circumstances, is the gravity retaining structure still safe and reliable? Until now, railways still lack of an integral safety evaluation system and technology of the retaining structure. This subject is suggested mainly based on<Research on the load schema distribution and safety evaluation technology of the gravity retaining structures>, an important research subject of the Ministry of Railways, which is linked closely with engineering practice. Therefore, it has the important theoretical significance and practical value.To evaluate the safety condition of existing gravity retaining structures, the safety confections method is often used before. However, this method is insufficiently comprehensive and cannot indicate the safety degree of the structures. At first, a great mass of literature were consulted to understand the study of safety assessment technique about the gravity retaining structures home and abroad. Then, based on the requirement of< Rules of Safety Evaluation>, a safety evaluation system was established with integral practice of the gravity retaining structures. What is more, elements of safety evaluation were determined by recognizing the dangerous and harmful factors of the gravity retaining structures. Finally, various safety assessment methods were discussed, especially for the reliability method, fuzzy comprehensive assessment method and expert assessment method, whose principles and procedures were expounded carefully with instances, respectively.This paper was attempting to evaluate the satiety conditions of the existing gravity retaining structures with a preliminary discussion about the safety assessment technique of them. In this way, the safety assessment report can be obtained, and what is more, maintenances and reinforcements were suggested to deal with the unsafely structures. It is quite necessary to maintain the structures'normal service life, decrease the accident rate and reduce the economic losses.