Analysis of the influence of lateral grouting points on deformation of shield tunnel under load

As a trenchless tunnel deformation treatment technology, the rectification grouting of shield tunnel has been applied in engineering, but there is no basis for the layout of rectification grouting points, and there is no relevant analysis. In order to analyze the influence of grouting correction point on tunnel deformation, the simulation model of lateral grouting is established based on indoor model test, and the influence of grouting correction point layout on shield tunnel is analyzed. On the basis of the established model, the unit horizontal axial force, additional earth pressure, diameter change and deflection deformation of tunnel under different working conditions are obtained by simulating various working conditions of single point and multi-point grouting mode. The main conclusions are as follows: (1) vertical elliptical deformation occurs in shield tunnel under horizontal load compression caused by side grouting, and horizontal deflection deformation occurs in shield tunnel to the opposite side of grouting at the same time;(2) the smaller the net distance between grouting point and tunnel, the greater the maximum horizontal earth pressure caused by grouting on tunnel side, but the smaller the influence range of additional earth pressure caused by grouting;(3) Uniform grouting at multiple grouting points is beneficial to uniform distribution of additional earth pressure and horizontal rectification of shield tunnel under the same grouting quantity;(4) In order to produce good horizontal rectification effect of side grouting tunnel, it is suggested to adopt simultaneous grouting at multiple grouting points, that is, grouting mode of "uniform distribution at multiple grouting points"