基于各向异性本构模型的隧道支护控制

为了采用传统的力学模型来描述各向异性条件下隧道的受力特征与变形分布规律,作者基于空间滑动面理论的各向异性弹塑性本构模型,通过C++编程形成动态链接库dll文件,进行了FLAC3D各向异性弹塑性本构关系的二次开发.模拟分析结果表明,在各向异性条件下,隧道锚杆受力呈非对称分布的状态,经破坏区锚杆加长后模拟分析,围岩塑性区明显减小,且锚杆受力趋向均匀.通过胶州湾隧道接线工程现场应用,基于各向异性本构关系的隧道关键区支护控制是可行的.

Tunnel Supporting Control Based on Anisotropic Constitutive Model

In order to describe the tunnel’s stress and deformation distribution by traditional mechanical model,the anisotropic elastic plastic model based on SMP was used,and through forming the dll file by programming with C++,the FLAC3D secondary development of anisotropic elastic-plastic model was conducted.Results obtained from the simulation analysis indicate that the stress distribution of the tunnel anchors is asymmetric under the anisotropic condition.When the anchors in the plastic zone are lengthened,the plastic zone of the surrounding rock decreases obviously,and the stress distribution of the anchors becomes uniform.Through field application in Sichuan Road connecting line project of Jiaozhou Bay Tunnel,the key zone supporting method based on the anisotropic constitutive relationship proves to be available.