软土地区盾构施工参数对土体位移影响的滞后性试验研究

发布时间：2018-03-05 02:28

本文选题：盾构参数　切入点：土体位移　出处：《岩土力学》2017年03期 　论文类型：期刊论文

【摘要】：由于软土地区深部地层超孔隙水压等因素存在,调整盾构参数对土体位移的影响往往具有一定的滞后性,该时段施工参数调整效应并不完全发生在当前时段,更多影响该断面土体的后期位移。在上海软土地区盾构施工现场设置两相同断面监测土体位移,在盾构施工不同阶段调整关键施工参数,分析各参数对土体位移扰动的时效性。在盾构靠近监测断面前调整土仓压力,穿越断面时调整掘进速度,在盾尾脱出时调整注浆量。通过监测数据以及关联系数时间效应分析得知,在盾构穿越断面时土体位移受前期调整的土仓压力的扰动影响,盾尾脱出时的土体位移体现穿越断面掘进速度所引起挤土效应改变,而后期固结阶段土体位移量体现出盾尾脱出时注浆量增大所带来稳定控制效应。因此,施工时不仅需关注当前土体变形,还应对参数调整后土体变形趋势预测给以足够重视,以避免因忽略滞后效应而导致事故发生。
[Abstract]:Due to the existence of factors such as excess pore water pressure in deep stratum in soft soil area, the influence of adjusting shield parameters on soil displacement is often delayed to a certain extent, and the adjustment effect of construction parameters in this period does not occur completely in the current period. In Shanghai soft soil area, two same sections are set up to monitor the soil displacement, and the key construction parameters are adjusted in different stages of shield construction. This paper analyzes the time-effect of each parameter on the disturbance of soil displacement, adjusts the pressure of soil bunker in front of shield construction near monitoring fault, and adjusts the tunneling speed when crossing the cross section. Through monitoring data and time effect analysis of correlation coefficient, it is known that the soil displacement is affected by the disturbance of pre-adjusted soil silo pressure during shield tunneling. The displacement of soil body during the exit of shield tail reflects the change of soil squeezing effect caused by the speed of tunneling through the cross section, while the displacement of soil in the later consolidation stage reflects the stable control effect brought by the increase of grouting quantity during the release of shield tail. In construction, attention should be paid not only to the current soil deformation, but also to the prediction of soil deformation trend after parameter adjustment, so as to avoid accidents caused by neglecting the lag effect.
【作者单位】：同济大学岩土及地下工程教育部重点实验室;同济大学地下建筑与工程系;上海城建市政工程有限公司;
【基金】：国家重点基础研究发展计划(973)项目:高水压越江海长大盾构隧道工程安全的基础研究(No.2015CB057800)~~
【分类号】：U455.43

【相似文献】