大直径泥水盾构穿越江堤的地表变形分析和控制研究

Research on Analysis and Control of Surface Deformation of River Embankment During Undercrossing of Large-diameter Slurry Shield

依托苏通GIL综合管廊工程,对大直径泥水盾构穿越江堤过程中的地表沉降实测数据进行分析,并采用数值模拟方法,建立了盾构隧道穿越江堤的数值模型。将模型计算结果与实测数据结果进行对比,验证数值模型的准确性。实测数据及数值模拟结果表明在盾构刀盘到达前,江堤地表会有轻微的隆起变形,而后随着盾构的推进,呈现下沉的趋势。影响因素分析结果表明注浆压力对江堤在盾构穿越后的变形影响显著,压力越高,堤顶最终的沉降值越小;而开挖面支护压力主要影响开挖面前方的地表变形,对堤顶最终的沉降值影响较小。

Based on the Sutong GIL utility tunnel project,through the analysis of the filed settlement monitoring data during the large-diameter slurry shield undercrossing the river embankment.The numerical simulation was used to establish the model of the shield tunnel undercrossing the river embankment.And the agreement between the field data and the numerical results validated this model.The monitoring data and numerical results show that before the arrival of shield cutter,the surface of the river embankment would uplift slightly,then subside with the advance of shield.The results of parameters analysis show that grouting pressure has a significant effect on the deformation of river embankment,especially after shield undercrossing.While the support pressure of excavation face mainly affects the surface deformation before excavation and has little influence on the final settlement value on the top of the river embankment.