Analysis Of Effect For Existing Buildings By Earth Pressure Balance Shield Construction In Beijing Subway

The construction of subway in Beijing is developing in such a scale never happened before, and the construction of new line for subway in Beijing is restricted by complicated environment nearby. It also inevitably needs to pass through or near the existing subway lines, bridges, underground pipelines, buildings etc. Urban subway construction projects not only to meet their own security, but also to ensure the safety and normal use of the surrounding environmental facilities, this made new demands for design and construction of project construction of new metro lines. Aiming at that feature mentioned above, combined with earth pressure balance shield project in Beijing subway pass through or near existing buildings etc, planning to use numerical analysis, the impact on existing buildings induced by shield tunnel construction will be assessed and analyzed.In this paper, the main research contents include:(1) Earth pressure balance shield tunnel construction technology and suggestions about shield selection in Beijing was analyzed, and numerical analysis method for analyzing actual projects was introduced.(2) Using FLAC3D, finite difference method which is the most common way of geotechnical engineering areas, numerical analysis was done combined with a project example refer to the impact on existing buildings induced by shield tunnel construction. At the same time, the settlement law of strata was analyzed in construction area compare with measured data in order to get the experience for project analyzing.(3) Combined with Beijing subway line 10 phasesâ…¡, prediction of impact on one existing building by shield tunnel construction was proposed, and suggestions for safety performance of existing buildings by numerical simulation and technical protection measures were given during shield tunnel construction.By theoretical analysis, numerical simulation indoors combined with monitoring in construction site, the previous ground displacement condition simulated by FLAC3D that uses finite difference method before, structural characteristics and mechanical properties of existing buildings and underground pipelines, compare to empirical formula, computer simulation and monitoring data analysis, additional impact on existing buildings can be predicted by numerical analysis, and this will provide a reference for safety assessment of risky projects of Beijing subway.