复合地层泥水盾构环流关键参数选择探析

Research on Mud Transportation Parameter Selection for Slurry Shield in Composite Strata

为研究复合地层泥水盾构泥水环流参数选择的问题,结合狮子洋隧道盾构工程,采用泥浆临界沉淀流速计算方法计算软弱地层和软硬不均地层所需的泥浆送、排量,并运用费祥俊模型试验公式进行验算。由于复合地层地质条件的复杂性,泥水盾构环流参数的影响因素较多,结合以上计算结果分析不同地层特性对泥浆送、排量的影响。研究结果表明:1)2种方法的泥浆送、排量计算结果相差不大,证明泥浆临界沉淀流速计算方法具有准确性和合理性;2)在软硬不均地层进行泥水盾构施工时,应加大泥浆送、排量,以减少输送颗粒在排浆管内滑移、平动,同时减少舱内积碴和泥浆管的磨损。研究结果可为复合地层下的泥水盾构施工提供参考。

In order to study the parameter selection for slurry circulation system of slurry shield in complex strata,the calculation method of critical flow velocity of mud are adopted to calculate delivery and discharge volume of slurry required for soft ground stratum and hard and soft strata by taking Shiziyang Shield Tunnel for example; and the Fei Xiangjun model test formula is used to verified the results. And then the influence of different formation characteristics on delivery and discharge volume of slurry is analyzed by calculation results. The results show that：（ 1） The results of mud flow obtained by the two methods are almost the same,so as to prove the accuracy and rationality of the calculation methods.（ 2） The delivery and discharge volume of slurry should be increased to make muck transport smoothly in slurry pipe,and reduce wear of slurry pipe when tunneling in hard and soft strata. The results can provide reference for the construction of slurry shield in composite strata of similar projects in the future.