The Applied Research Of Monitoring Buildings Cracks And Subsidence In Shield Passing Construction

In recent years, with the accelerating process of urbanization in China, the urban landscape is constantly expanding, and extending to the upper and underground space, which leads to the increasing urban construction density, the construction space is compressed. In density urban area, metro tunnel construction will inevitably cause strata movement and deformation, and then cause damage to the adjacent buildings. In city, it is a big concern for engineer to obtain the buildings subsidence rule due to construction of shield tunnel and to gain the real-time settlement information of building automatically, and then use them to evaluate or estimate the safe state of buildings.This article will take a underground water reservoir engineering in a shield construction for example, then analyze the influence caused by the tunnel construction beneath a building. It mainly includes the following four aspects:(1) Research and summary analysis, monitoring and forecasting method of surface and existing building deformation in tunnel underpass both at home and abroad. Through collecting and reading relevant literature and data, summary and study of existing research results in the field Knowledge and application of relevant theory.(2) Numerical simulation and calculation of the construction process of the shield tunnel under the water reservoir by element software, determining the importance of monitoring and monitoring to determine the threshold according to the calculations.(3) Calculation theory of settlement of settlement joint are based on long range macro strain making use of FBG strain sensing technology with long distance, and its reliability and accuracy are verified by laboratory experiments. On the basis of this, Precise and real-time monitoring method of settlement joints are advanced.(4) By using of FBG strain sensing technology with long distance, the concrete crack is being monitored constantly and accurately, so the construction company and the owners could have time to adjust and avoid further consequences. What’s more, the structural settlement is tested real-time and effectively by using fiber Bragg grating static leveling system. It has been limited to use widespread because of its high cost.