考虑主应力偏转的隧道松动土压力计算方法  

Calculation method of tunnel relaxed soil pressure considering deflection of principal stress

作　　者：黎春林 LI Chunlin(Institute of Civil and Architectural Engineering,Tongling University,Tongling 244061,China)

机构地区：[1]铜陵学院建筑工程学院,安徽铜陵244061

出　　处：《河海大学学报(自然科学版)》2025年第2期107-114,共8页Journal of Hohai University(Natural Sciences)

基　　金：安徽省自然科学基金项目(1808085ME162);安徽省高校学科(专业)拔尖人才学术资助项目(gxbjZD2022068);铜陵学院2020年度校学术带头人科研项目(2020tlxyxs19)。

摘　　要：为研究主应力偏转对隧道松动土压力的影响,基于大主应力拱迹线,针对实际工程中常见的塔式(三角形)滑裂面和盆式滑裂面两种情况下的侧压力系数分别进行了分析,提出了考虑主应力偏转角度的侧压力系数计算公式,并根据处于极限平衡状态土体微单元的受力平衡,推导了隧道拱顶松动土压力计算公式。与太沙基松动土压力计算公式相比,提出的松动土压力计算公式中删除了影响因素较多且难以准确取值的土体侧压力系数,代之以对松动土压力影响较大、与工程施工及土质参数密切相关的主应力偏转角度;对于黏性土,相比现有的松动土压力计算方法,该公式不需要进行坐标平移或者采用迭代法计算侧压力系数,提高了计算效率和精度。案例分析结果表明,该公式要显著优于太沙基松动土压力计算公式,其计算值与试验值吻合较好。To study the influence of the principal stress rotation on the relaxed soil pressure of tunnels,based on the trajectory of the major principal stress arches,the lateral pressure coefficients under the tower-shaped(triangular)and basin-shaped sliding failure surfaces were analyzed for common project scenarios in actual engineering projects.The lateral pressure coefficient calculation formulas considering the principal stress rotation angle were proposed.According to the force balance of the soil micro-element in the limit equilibrium state,the calculation formula of the relaxed soil pressure at the tunnel crown was derived.Compared with the relaxed soil pressure calculation formula of Terzaghi,the proposed formula for calculating relaxed soil pressure does not contain the soil lateral pressure coefficient,which has multiple influencing factors and tends to be challenging to accurately calculate,and instead substitutes it with the principal stress rotation angle which has a significant impact on the relaxed soil pressure and is closely related to the engineering construction and soil properties.This is especially true for cohesive soils when compared to existing formulas.For relaxed soil pressure,the proposed formula does not require using iterative methods and coordinate translation to calculate the lateral pressure coefficient,thereby improving computational efficiency and accuracy.The case study results demonstrate that the algorithm presented in this paper is significantly superior to Terzaghi’s approach,with estimated values aligning well with experimental measurements.

关 键 词：松动土压力 主应力偏转 大主应力拱 侧压力系数 隧道 

分 类 号：TU452[建筑科学—岩土工程]