复合地层双模盾构适应性及掘进参数研究

依托南宁市轨道交通5号线五一立交站—新秀公园站区间隧道工程,论述了土压–泥水双模盾构的选型依据,基于区间右线双模盾构及左线泥水盾构的现场掘进试验数据,详细对比分析不同地质段和不同模式段的掘进参数变化及能源消耗情况,得出相比于单模式盾构,双模盾构在复合地层条件下的适应性。研究结果表明:始发段由粉土、粉细砂与圆砾组成的复合地层中采用的泥水平衡模式严格控制地面沉降,在过江段所在的全断面粉砂质泥岩和泥质粉砂岩复合地层中,土压模式有效规避了泥水盾构易固结泥饼的风险;掘进速率方面,右线双模盾构相对于左线掘进速率增幅达181.44%;能源消耗方面,右线双模盾构的盾尾油脂消耗、水消耗及电消耗较左线分别减少了7.87%,30.32%,30.64%。

Tunneling parameters and comparison of adaptability for compound strata of dual-mode shield machine

Based on the tunnel project between Wuyi Interchange Sation and Xinxiu Park Station of Nanning rail transit line 5,firstly the selection basis of the earth pressure-slurry dual-mode shield is discussed,and then,according to the field excavation test data of the right line and left line slurry shield,changes of excavation parameters and energy consumptions of different geological sections and different mode sections are analyzed.Compared with that of single-mode shield,the adaptability of dual-mode shield in composite strata is analyzed.The results show that the slurry-balanced mode used in the composite stratum consisting of silt,silty fine sand and round gravel in the initial section strictly controls the land subsidence,and the earth pressure-balanced mode effectively avoids the risk of clay formation in the composite stratum consisting of full fault silty mudstone and argillaceous siltstone in the river-crossing section.In terms of the excavation rate,the rate of dual-mode shield is 181.44%higher than that of the slurry shield of the left line.In terms of energy consumption,the oil consumption of the shield tail,water consumption and electricity consumption of the dual-mode shield of the right line are 7.87%,30.32%and 30.64%lower than those of the left line,respectively.The research results may provide a reference for the study on driving parameters and selection adaptability of double-mode shield in composite strata.