坝陵河大桥隧道锚围岩力学特性原位试验研究

In situ tests on mechanical properties of rock surrounding tunnel-type anchors of Balinghe Bridge

为全面认识坝陵河悬索桥西岸隧道锚的受力变形特性及安全稳定性,在分析研究锚碇区地层岩性特点基础上,利用相似性原理设计了与锚碇系统实际受力状态相适应的隧道锚原位模型试验系统,研究了原位试验加载及测试方法.试验成果表明,锚塞体混凝土和岩体在不同岩体条件下呈现出不同的变形特点:当岩体质量较好时,变形基本呈线性变化;当锚塞体周围岩体质量较差时,岩体的非线性变形特征明显.锚塞体与岩体之间的剪切残余变形表明锚塞体和岩体接触面在设计荷载作用下将产生较大的相对滑动.完整性较差岩体中的锚塞体变形远大于完整性较好情况下的锚塞体变形.

In order to fully understand the deformation characteristics and stability of tunnel-type anchorages at the west bank of the Balinghe Suspension Bridge, an in situ model test system in accordance with the actual mechanical status of the tunnel-type anchorages was designed using the similarity principle based on the analysis of the rock properties of the strata in the anchorage area. The loading and test methods for the in situ tests were studied. The test results indicate that the rock mass and anchoring concrete-plug exhibit different deformation characteristics under different rock mass conditions. With a high-quality rock mass, the deformation is basically linear, and when the quality of the rock mass is lower, the deformation of the rock mass is non-linear. The shear residual deformation between the rock mass and the anchoring concrete-plug shows that a relatively large slip will occur on the contact surface under the design load. The deformation of the anchoring concrete plugs in a rock mass with good integrity is smaller than that of the anchoring concrete plugs in a rock mass with less integrity.