基于Hoek-Brown屈服准则的修正纵向变形曲线分析

发布时间：2018-03-11 08:23

本文选题：纵向变形曲线　切入点：隧道　出处：《地下空间与工程学报》2017年S1期 　论文类型：期刊论文

【摘要】：围岩纵向变形曲线反映了开挖面附近因隧道开挖而引起的围岩变形,目前最为常用的纵向变形曲线拟合公式并不能有效反映多种质量围岩的变形情况。针对该问题,根据有限差分软件FLAC3D建立了三维隧道开挖模型,基于Hoek-Brown屈服准则得出了不同工况理想弹塑性围岩的纵向变形曲线,通过对数值模拟计算结果进行非线性回归分析,得到了修正的纵向变形曲线拟合公式,并探讨了不同质量围岩条件下开挖面附近的位移释放率。结果表明:对于质量较差的围岩,在开挖面后方,原有的拟合公式会在较大程度上高估位移释放率,低估施加于支护上的荷载,相应的支护设计偏不安全。
[Abstract]:The longitudinal deformation curve of surrounding rock reflects the deformation of surrounding rock caused by tunnel excavation in the vicinity of excavating surface. The most commonly used fitting formula of longitudinal deformation curve can not effectively reflect the deformation of surrounding rock with various mass. According to the finite difference software FLAC3D, the 3D tunnel excavation model is established. Based on the Hoek-Brown yield criterion, the longitudinal deformation curves of the ideal elastoplastic surrounding rock under different working conditions are obtained, and the nonlinear regression analysis is carried out on the results of the numerical simulation. A modified fitting formula of longitudinal deformation curve is obtained, and the displacement release rate near the excavation surface under different mass surrounding rock is discussed. The results show that: for the poor mass surrounding rock, behind the excavated surface, The original fitting formula overestimates the displacement release rate to a large extent, underestimates the load applied on the support, and the corresponding support design is not safe.
【作者单位】：华中科技大学岩土与地下工程研究所;
【基金】：国家自然科学基金(51678267)
【分类号】：U451.2

【参考文献】