隧道开挖地层位移计算方法及工程应用  

A Method for Calculating the Ground Displacements Induced by Tunnel Excavation and Its Application in Field Engineering

作　　者：史磊磊 何海琦 林庆涛 SHI Leiei;HE Haiqi;LIN Qingtao(Key Laboratory of Urban Security and Disaster Engineering of Ministry of Education,Beijing University of Tech-nology,Beijing 100124,China;Beijing Municipal Construction Group Co.Ltd,Beijing 100089,China;School of Civil Engineering,Tsinghua University,Beijing 100084,China)

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [2]北京市政建设集团有限责任公司,北京100089 [3]清华大学土木水利学院,北京100084

出　　处：《防灾减灾工程学报》2023年第6期1224-1233,共10页Journal of Disaster Prevention and Mitigation Engineering

基　　金：国家自然科学基金项目(52025084;52208396;52278385);中国博士后科学基金面上项目(2021M701934);北京市教委科技一般项目(KM202210005019)资助。

摘　　要：经验方法是计算隧道开挖引起地层位移的重要方法,尤其是当地层的非线性塑性变形显著时,经验方法可更为合理地描述地层的位移分布规律,但是可实现地层竖向位移和水平位移统一计算的方法尚未建立。基于隧道上方土体单元的运动特征,提出了隧道开挖引起的地层位移的经验计算模型,建立了地层水平位移和竖向位移之间的关系。通过分析25组现场工程数据,优化了隧道上方地层最大沉降Sv,max(z)的公式,结合已有的沉降槽宽度系数i(z)的公式,发展了Peck-Mair公式,实现了隧道上方地层竖向位移场的合理计算。根据地层水平位移和竖向位移之间的关系,基于发展的Peck-Mair公式,推导了地层水平位移的计算公式,实现了地层竖向位移和水平位移的统一计算。在地层水平位移计算公式中,变量H(z)表示土体运动定向点位置随深度的变化规律,基于工程实测结果提出了一个对数函数实现了H(z)的定量描述。利用伦敦HEX隧道工程中实测的2组地层位移数据,验证了所提地层位移计算方法的合理性。最后,将提出的地层位移计算方法应用在北京地铁12号线安-安区间渡线段隧道开挖工程,实现了该工程中隧道开挖引起的地层位移场的反演。The empirical method is very important to calculate the ground displacement caused by tun-nel excavation,especially when the non-linear plastic deformation of stratum is significant.However,a unified method for calculating the vertical and horizontal displacements of the ground has not been es-tablished.An empirical model for calculating the ground displacement induced by tunnelling is pro-posed by assuming the movement vector of the soil.Then,the mathematical relationship between the horizontal displacement and the vertical displacement of the soil is established.By analyzing 25 sets of data from field engineering,the formula for the maximum settlement,Sv,max(z),is optimized.A devel-oped Gaussian function is obtained by combining the existing width coefficient of the settlement trough,i(z),and the optimized maximum settlement,Sv,max(z),to describe the vertical displacement of the ground.Then the formula for the horizontal displacement is presented based on the developed Gaussian function.H(z),representing the position of the oriented point of the soil movement is a vari-able in the horizontal displacement formula.Based on the measured results,a logarithmic function is proposed to describe the variation of H(z)with depth in a clay stratum.Then,the rationality of the proposed method is validated using 2 sets of data from the field project.Finally,the proposed method is applied to the tunnel from Anzhen Bridge to Anhua Bridge on Beijing Metro Line 12,and the ground displacement field caused by the tunnel excavation in the project is successfully inverted.

关 键 词：隧道开挖 地层变形 竖向位移 水平位移 经验方法 Peck-Mair公式 

分 类 号：U452[建筑科学—桥梁与隧道工程]