隧道锚围岩拉拔模型试验研究及数值模拟

采用现场模型试验同FLAC3D数值试验相结合进行对比研究。介绍了坝陵河大桥西锚碇1:20、1:30现场模型试验，研究发现锚碇横截面位移呈马鞍型，向两端逐渐收敛，轴线方向呈梯形分布，围岩残余变形率呈V形分布，相同应力水平下，大尺寸模型的监测位移较大。数值试验发现，应力分布具有明显的分段特征，沿锚体呈不对称分布，可能的破坏方式是锚体带动周边一定范围岩体发生塞体状的整体拉剪复合破坏。设计和施工过程中应对显著变形区及破损区内的岩体进行重点加固。

Pull-out model test for tunnel anchorage and numerical analysis

In-situ pull-out model test and numerical analysis FLAC3D are integrated to study the mechanical behaviors of tunnel anchorage. The in-situ model test of west anchorage of Baling River Bridge is introduced in detail. According to the model test, it is found that the displacement of cross-section shows saddle-shaped, and trapezium-shaped along the axes. The rate of residual displacement appears V-shaped. The monitoring displacement of large scale model is bigger than that of the small one. From the numerical analysis, it is found that the stress distribution shows subsection character, and the stress distributes unsymmetrically along anchorage. And plug-shaped tensile-shear complex failure caused by anchorage in surrounding rock may be a failure mode. The rock mass in damage zones and prominent deformation zones should be paid more attention to during design and construction.