盾构开挖面楔形体支护压力模型分析及改进  

Analysis and Improvement of Wedge Supporting Pressure Model of Shield Tunnel Excavation Face

作　　者：赵文[1] 程诚 李慎刚 徐行[1] 朱林 

机构地区：[1]东北大学资源与土木工程学院,辽宁沈阳110819

出　　处：《中国公路学报》2017年第8期74-81,90,共9页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51578116)

摘　　要：为了维持砂土地层盾构隧道开挖面的稳定性,以楔形体模型2种常用的面积等效方法为出发点,对开挖面支护压力计算公式进行推导,同时结合现有楔形体模型与Takano 1g模型试验结果从砂土盾构开挖面破坏区外形的角度改进楔形体计算模型,在考虑松动土压力的情况下提出盾构开挖面主动极限支护压力的计算公式并简化。将Chambon离心模型试验结果与楔形体支护压力计算结果进行对比,并依托西安盾构隧道工程土舱压力监测数据对新公式进行工程应用分析。研究结果表明:采用第1种面积等效方法时的楔形体模型计算结果更为精确,不同模型计算结果出现差异的主要原因来自于楔形体竖直侧面摩擦力的影响,同时提出1.5倍所提简化公式的计算值作为上部土舱压力设定的建议值。To maintain the stability of the excavation face of the shield tunnel in sandy soils,the equation for supporting pressure of the excavation face was deduced based on two common area equivalent methods of wedge model.Whilst,the wedge calculation model was developed from the aspect of the failure shape of the shield excavation face in sandy soils,combined with existing wedge models and results of Takano 1g model tests.A new equation of active limit supporting pressure of the shield excavation face,in consideration of loosening soil pressure,was proposed and simplified.The results of Chambon centrifuge model tests and all equations were compared and the application of new formula according to the monitoring data of earth chamber pressure of Xi＇an shield tunnel engineering was analyzed.The results show that calculation results of wedge model obtained by the first area equivalent method are more accurate.The influence of friction acting on wedge vertical surface is the main factor for differences between various calculation results.And the 1.5times calculated value of simplified equation in this paper is proposed as recommend value of upper earth chamber pressure.

关 键 词：盾构隧道 支护压力计算公式 面积等效 主动极限 楔形体计算模型 砂土盾构开挖面 

分 类 号：U455.43[建筑科学—桥梁与隧道工程]