中文摘要：

基于宜昌伍家岗大桥隧道锚工程区的特定地质条件,采用室内三维地质力学模型试验技术,通过后推超载的方法,研究锚塞体与围岩从加荷到破坏的整个过程与整体稳定性。依据相似理论,按照1∶40大比尺对锚塞体及不同岩层的岩体力学特性进行相似模拟,研究锚塞体与围岩的联合受力变形特征、失稳破坏过程、破坏形态以及超载能力,对其整体稳定安全度进行评价。通过分析隧道锚在设计荷载和超载作用下的变形特征及裂缝产生、扩展及汇通的全过程规律,研究隧道锚变形破坏机制及其与围岩联合承载的夹持效应。试验结果表明：在设计荷载作用下,锚体及围岩后表面变形曲线呈双峰形对称,以对称中心向四周呈马鞍形衰减扩散,前表面变形曲线与后表面相似,后表面变形大于前表面变形,隧道锚与围岩体处于弹性阶段;在多倍设计荷载超载条件下,锚塞体与围岩相互作用,共同抵抗外力,形成夹持效应,锚体周边1.0-1.5倍后锚面宽度范围内的围岩变形量较大,综合分析认为隧道锚的超载稳定系数取9.0。

英文摘要：

In order to reveal mechanism and the global stability of Wujiagang yangtze river bridge tunnel-type anchorages,the deformation characteristics and the potential failure mode of surrounding rockmass,a 3D geomechanical model test with the similar scale of 1∶40 for tunnel-type anchorage was carried out. Base on the similarity theory,the complex geological structures including anchor plug body and different rock mass are simulated. Through the overloading destructive model test,the deformation characters,the failure process,the pattern and mechanism of tunnel-type anchorages and surrounding rockmass are obtained. The test results show that the deformation characteristic curves at the rear surfaces of anchorages and surrounding rockmass present symmetrical bimodal shape,and those of the frontal surfaces present the shape of convex upward. The deformations at the rear surface are greater than those at the frontal surface. Because of the clamping effect,the amount of deformation in the surrounding rock range 1.0 to 1.5 times width of anchorages rear surface is large. After comprehensive analysis,the global stability coefficient of tunnel-type anchorages is considered to be 9.0.