盾构在高水压粉砂地层中大直径长距离掘进关键技术应用研究

Application of Shield in Large Diameter Long-distance Excavation in High Pressure Silt Formation

为解决盾构在高水压粉砂地层中大直径长距离掘进中可能存在的风险难题,以南水北调中线穿越黄河段工程为例,分析工程潜在风险,对施工过程中各项参数(推力、速度、泥水压力等)进行计算分析,并用Midas/GTS软件进行有限元分析,研究了盾构在高水压粉砂地层中大断面长距离掘进过程中地层、管片位移变化规律,得出了大断面长距离掘进过程中管片附加应力变化规律以及地层应力变化规律。结合相关南水北调穿黄工程监测数据,验证了模型的可靠性。

In order to solve the possible risk problems of shield in the long-distance excavation of large diameter in high-pressure silt strata,taking the middle line of the South-to-North Water Diversion through the Yellow River as an example,the potential risks of the project are analyzed.Based on the calculation and analysis of various parameters(thrust,velocity,mud pressure,etc.)in the construction process,and the finite element analysis using Midas/GTS software,the displacement of the strata and tubes during the long-distance excavation of the shield during the long-distance excavation of large sections of high-pressure silt strata was studied.The change of additional stress and formation stress in the process of large section long distance excavation are obtained.The reliability of the model is verified by combining the monitoring data of the relevant South-North Water Diversion Yellow project.