Risk assessment of construction of excavations in areas of rock and soil

With the acceleration of economic development and urbanization, some cities in rock areas, such as Qingdao, Dalian and Chongqing, has launched rail?transit?construction to improve the urban traffic conditions. Different from soft soil areas, construction risk of excavations of subway stations in rock areas is affected by various uncertain factors with random and fuzzy behaviors. Based on the subway station construction of Qingdao Subway Line No. 3 Project, a synthetic evaluation index system for excavation construction risk of subway stations in rock and soil areas is established by analyzing the factors that influence subway station construction with the fault tree method. A model of three-stage fuzzy synthetic evaluation on the basis of analytic hierarchy process and fuzzy method is adopted to assess excavation construction risk of the subway station. The analytical results show that the proposed method is practical and helpful to other similar projects.