摘要
为研究S形空间曲线顶管隧道施工引起的地表沉降规律,基于Mindlin弹性力学解和随机介质理论,构建S形空间曲线顶管施工引起的地表沉降计算模型,获得顶管施工各参数和空间曲线段施工地层损失引起的沉降规律,并与宁波市潘桥变电站顶管隧道工程地表沉降实测值进行对比验证。研究结果表明:1)考虑顶管施工引起的附加荷载、水平与竖向超挖间隙等因素所构建的S形空间曲线顶管施工引起的地表沉降计算方法,理论计算值与实测值吻合较好,能够对地表沉降进行较为准确的预测;2)空间曲线顶管施工引起的地表沉降槽不以顶管中心轴线对称,在顶管机头无超挖刀参与掘进的情况下,最大沉降值向弯道外侧偏移,且顶管机平面转弯产生的超挖间隙对沉降槽偏移影响最大;3)在S形空间曲线顶进时,地层损失是造成地表沉降的主要原因,应严格控制注浆参数,理论注浆量应包括环形空隙与超挖间隙注浆量体积之和。
To investigate the behavior of surface settlement caused by S-shaped spatially curved pipe jacking for tunnel constructions, a calculation method is proposed to obtain the surface settlement caused by S-shaped spatially curved pipe jacking, based on Mindlin′s elastic solution and the random medium theory. The surface settlements are obtained in the construction of the spatially curved section considering various parameters of pipe jacking and formation loss. The calculated results are compared with the measured surface settlements of the pipe jacking tunnel project of Panqiao substation, Ningbo, China. The results show that:(1) By considering the additional load caused by pipe jacking and horizontal and vertical overbreak clearances, the results from the proposed method agree well with the measured results,indicating that the proposed method can accurately predict the actual surface settlement.(2) The surface settlement groove caused by spatially curved pipe jacking is not symmetrical with respect to the central axis of pipe jacking. When there is no overbreak cutter on the cutterhead, the maximum settlement shifts to the outside of the curve, and the overbreak gap generated by plane turning of the pipe jacking machine can dramatically affect the deviation of the surface settlement groove.(3) During the pipe jacking process, the stratum loss causes most of the surface settlement. Therefore, the grouting parameters should be strictly controlled, and the theoretical grouting amount should be the sum of the grout volumes within the annular and over the excavation gaps.
作者
许有俊
孟毅欣
张朝
韩志强
郭飞
高胜雷
XU Youjun;MENG Yixin;ZHANG Chao;HAN Zhiqiang;GUO Fei;GAO Shenglei(School of Civil Engineering,Inner Mongolia University ofScience and Technology,Baotou 014010,Inner Mongolia,China;Academician Workstation of Mine Safety andUnderground Engineering,Inner Mongolia University of Science and Technology,Baotou 014010,InnerMongolia,China;Engineering Research Center of Urban Underground Engineering at Universities of InnerMongolia Autonomous Region,Inner Mongolia University of Science and Technology,Baotou 014010,InnerMongolia,China;Beijing Municipal Construction Group Co.,Ltd.,Beijing 100079,China)
出处
《隧道建设(中英文)》
CSCD
北大核心
2023年第1期48-57,共10页
Tunnel Construction
基金
国家自然科学基金(51868062)
北京高新市政工程科技有限公司横向课题(2020012)。