隧道开挖对临近单桩及群桩承载性状影响的数值分析  

Numerical Analysis of the Effect of Tunnel Excavation on the Bearing Properties of Adjacent Single Piles and Group Piles

作　　者：陈昌盛 CHEN Changsheng

机构地区：[1]贵州省有色金属和核工业地质勘查局七总队,贵州贵阳550000

出　　处：《重庆建筑》2025年第4期85-89,共5页Chongqing Architecture

摘　　要：为研究盾构隧道开挖对临近单桩及群桩承载性状的影响,基于ABAQUS数值模拟,采用Mohr-Coulomb弹塑性本构,建立三维计算模型,系统分析了非均质土中隧道开挖对邻近单桩和群桩内力和变形的影响。结果表明:1)在非均质上软下硬的土体结构层中,隧道开挖所引起的单桩桩顶会产生较大的水平变形,且单桩在上软下硬土层中的沉降明显大于上硬下软土层中的位移;2)非均质土中隧道开挖对群桩内力的影响明显大于对单桩变形影响;3)与均质土相比,各层土的刚度差异性越大,桩体沉降变形越大。实际工程中,在上软下硬的土层中,应重视桩顶沉降变形的监测与支护。对于上层软土,施工中可采取注浆加固的方法以提高软土刚度。To investigate the impact of shield tunnel excavation on the bearing behavior of adjacent single piles and pile groups,a three-dimensional numerical model was established in ABAQUS using the Mohr-Coulomb elastoplastic constitutive model.The study systematically analyzed the influence of tunnel excavation on the internal forces and deformations of nearby single piles and pile groups in heterogeneous soil.The results indicate that:(1)In stratified soil with a soft upper layer and a stiff lower layer,tunnel excavation induces significant horizontal displacement at the pile head,and the settlement of a single pile in soft-over-hard soil is noticeably greater than that in hard-over-soft soil;(2)Tunnel excavation in heterogeneous soil has a more pronounced effect on the internal forces of pile groups than on the deformation of single piles;(3)Compared with homogeneous soil,the greater the stiffness contrast between soil layers,the more severe the pile settlement and deformation.In practical engineering,in strata with soft upper and stiff lower layers,special attention should be paid to the monitoring and support of pile head settlement and deformation.For soft upper layers,grouting reinforcement can be used during construction to enhance the stiffness of the soft soil.

关 键 词：隧道开挖 临近桩基 内力和变形 数值模拟 

分 类 号：TU473[建筑科学—结构工程] U45[建筑科学—土工工程]