Research Of The Strata Deformation Rule Of Shallow Rock And Large Span Tunnel In City Constructed Using Drill-Blasting Method

With the rapid development of China's urban infrastructure construction, the drill-blasting method has been widely applied in highway, railway tunnel and underground railway, underground pipelines construction etc,because of its advantages of flexiblity and adaptablity. It's inevitably to cause a disturbance of the surroundings and the deformation of Strata ,which resulting in a series of problems ;Especially in city tunnel construction, it will affect even endanger the normal use and safety of the tunnel structure itself and the neighboring buildings, roads, pile foundation and underground pipeline etc . Therefore, to seek the law of strata deformation in the process of construction has very important academic value and engineering application value.This paper makes a thorough study on the strata deformation caused by the tunnel construction ,based on the the analysis of connecting engineering of Qingdao jiaozhou bay undersea tunnel and through regression analysis of on-site monitoring data. The main work has been done is as follows:1,This paper studies the deformation mechanism of the ground displacement and the crown displacement of the tunnel in the construction process with the drill-blasting method.2,According to the different level of surrounding rock, combined with the on-site monitoring data, a detailed analysis is studied in Qingdao rock tunnel radius is changing with time in V, rock and level IV of the linear distribution in grade II, a logarithmic function distribution in the rock. Also studied the effect of surface deformation of rock vaults, determines the effect of surface of surrounding rock in V, roughly doubled hole diameter, for the level IV to 1.5 times of the hole in the rock, grade II to 2.5 times hole diameter.3,This paper analyzes and studys detailedly the ground lateral deformation of the tunnel and determines the influnce level and range of ground caused by the tunneling in different surrounding rock and buried depth, according to the different level of surrounding rock, combined with the on-site monitoring data.4,Through the analysis of the monitoring data, the relational expression between vault sink and surface subsidence at tunnel excavation and the buried depth of tunnel is found out:I = 4.63e^-0.317hU...