Visual C++ Based Risk Assessment System for Ground Environment Damage Induced by Subway Tunneling

In all environmental damages induced by subway tunneling excavation, the prediction and control of the ground surface settlement are the important problems to have to be solved. Therefore, combined with geographic information system (GIS), a new Subway Tunneling-induced ground-Environment-damage Assessment and control Design system, named STEAD, is developed and introduced. Subway Tunneling-induced ground-Environment-damage Risk assessment subsystem (STEAD-RISK) is a part of STEAD. This paper presents the development and application of STEAD-RISK. The developed subsystem employs stochastic medium theory and Peck prediction method, and is written in the Visual C++ program. The subsystem has the function of inputting monitoring data or predicting data by analyzing of computer to Access database, then exchanging data by Access database. STEAD-RISK includes three function menus for risk assessment: a) controlling of the surface deformation monitoring, is analyzed respectively from shield method, shallow-buried tunneling method and open cutting and shaft sinking method; b) controlling of the building foundation deformation, is divided into overall inclination of multi-storey and high building, partial incline of bricking-up bearing structure's foundation and adjacent isolated subsidence of frame structure's foundation; c) influence subarea and safety classification in tunnel and foundation pit of the project. The developed subsystem permits users to identify potential risk areas by combining with graphics and text. STEAD-RISK has successfully applied to many construction site of subway, such as Guangzhou subway line No.2 and No.3, Beijing subway line No.4 and No.10. The applications demonstrated that STEAD-RISK can be used as an efficient tool in the perspective of tunneling-induced ground-environment-damage risk management for tunneling projects in urban areas. Finally, its practical significance t is also discussed.