地铁盾构机掘进对周围环境影响的现场测试研究

研究目的:盾构机在城市地铁建设中得到了广泛的应用,但在盾构掘进过程中会引起地层损失,过大的地层损失,可导致较大的地面沉降,对地面建筑物、地下管线等设施产生不利影响甚至会导致破坏,引起较大的经济损失。为此,本文以南京地铁一号线为依托,对盾构掘进过程中引起的建筑物、地下管线位移以及引起的地下水位进行了现场测试,经过分析、总结,得到了盾构掘进对周围环境影响的规律性结论。在此基础上,从地层沉降与土仓压力、同步注浆量和出喳量的关系,探讨了地层沉降的控制措施。研究方法:对盾构掘进过程中所影响得到地下管线位移、建筑沉降、地下水位变化等进行现场实测,获取了有关现场测试数据,并对这些数据进行分析,得到可以供施工参考的有价值的结论。研究结论:调整、修正、合理匹配盾构掘进参数,建立有效土压平衡,确保同步注浆效果,是控制地层损失,减小地层变位的有效手段,是减少盾构掘进对周围环境影响的重要措施。

Research on Impact of Shield Tunnelling on Surrounding Environment of Tunnel

Research purposes: Nowadays shield machine is widely used in metro construction.However,the much loss in stratum may occur during shield tunnelling and too much loss in stratum may cause big-scaled surface subsidence,resulting in bad impact on the ground buildings and underground pipelines,even damaging them with big economic loss.Taking the Line 1 of Nanjing Metro as an example,the site tests are done for the displacements of buildings and underground pipelines and changes of underwater level during shield tunnelling,and through making analyses of them,the regularities of impact on the surrounding environment are obtained.Considering the relations between stratum subsidence and soil pressure in soil chamber and between synchronous grouting volume and discharging waste soil volume,the discussion is made on the preventive measures for control of stratum subsidence.Research methods:The site tests are done for the displacements of buildings and underground pipelines and changes of underwater level during shield tunnelling and through making analyses of these tested data,the valuable conclusion is obtained for reference to construction.Research conclusions:Modification and right choice of the parameters for shield tunnelling,keeping effective balance of soil pressures and ensuring the effect of synchronous grouting are the effective means and important measures for control of the loss in stratum and reduction of displacement of stratum and impact of shield tunnelling on the surrounding environment.