ABSTRACT
Passing the shield tunnel underground will cause settlement and deformation of the building, and in severe cases, it will cause damage to the pile foundation and even disasters. In order to study the settlement law of the pile foundation of adjacent buildings when the shield tunnel is under construction, taking the construction site of Shuxiang Primary School under the shield tunnel of Shenzhen Rail Transit Line 6 as an example, a three-dimensional rock-soil mass-tunnel-pile foundation was established in combination with the site. Through Numerical calculation model, the simulation results show that: When the stratum is not reinforced, the maximum settlement value of the pile foundation is 46.06mm, which exceeds the control standard after the stratum is grouted with the sleeve valve pipe and the rotary jet pile; when the stratum is reinforced, the maximum settlement value of the pile foundation is 11.07mm., which is about 75% less than the unreinforced case, meeting the building pile foundation control standard; the maximum settlement value of the pile foundation obtained by on-site monitoring is 10.93mm, which is similar to the simulation result. Numerical simulation and on-site construction results indicate that the above reinforcement method can effectively control the impact of shield tunnel and reduce the impact of shield tunnel on pile foundation settlement. The settlement values of the ground and pile foundation obtained by numerical simulation are similar to the settlement values obtained by actual monitoring, and the change trend is consistent, which can provide an effective soil reinforcement scheme for shield construction. Pile foundation settlement control has good reference value and guiding significance.
