Influence of Pipe Jacking on Stress and Deformation of Existing Subway Tunnels
To study the influence of the pipe jacking on the stress and deformation of the existing adjacent subway tunnel struc-tures,this paper presents the numerical analysis results.The construction site environment,construction process,construction method and existing protection requirements of the subway structure are considered and the displacement and internal force of the subway tunnel structure under the relevant construction staging are simulated by using Midas GTS/NX software.Combined with the actual monitoring data,the safety evaluation of the pipe jacking construction method performed.The results show that the influence of the pipe jacking can be classified as the first class.The displacement in the Y direction(jacking direction)and the Z direction(vertical direction)of the subway structure after the entire pipe jacking construction process is 0.138 mm and 0.549mm respectively.The change rate of the force is not more than 3％,and the structure is still working within the tolerable range.From the real-time monitoring data,the maximum displacement of the subway structure in the Y direction and the Z di-rection is 1.76 mm and 0.65mm,respectively.The monitoring data is in a good correspondence with the simulation results,showing that the change of the tunnel structure affected first is greater than that of the tunnel structure affected later.Both the monitoring and the simulated displacement of the tunnel structure do not exceed the recommended 7mm,that is,the entire pro-ject is safe to advance under the normal construction conditions.
万方数据
维普
