全长黏结注浆格构锚固工程模型试验研究

Model test on fully grouted lattice beam anchorage

格构锚固工程在滑坡防治中的应用已越来越广泛,但其作用机制研究却远滞后于实际应用。针对全长黏结注浆工况下格构锚固工程的受力情况、破坏模式及作用机制,开展格构锚固工程大型物理模型试验。试验结果表明,全长注浆格构锚固可有效提高滑坡的稳定性;锚固力在滑面处最大,向两端递减,格构所承受锚固力很小,其基底反力呈跨中大节点小的近三角形分布;锚杆在滑面位置发生剪切变形,格构仅发生轻微挠曲变形,滑坡体发生整体滑移;锚杆发挥剪切抗滑作用,为主要抗滑构件,格构则保证了滑坡的整体稳定性;全长注浆工况格构锚固设计应注重校核锚杆的抗剪切能力,格构部分建议采用构造配筋设计。试验研究结果揭示了全长黏结注浆工况下格构锚固体系的力学抗滑机制,可供其他类似工程参考和借鉴。

Lattice beam anchorage has been applied more and more widely in the landslide prevention, but its mechanism research is lagging far behind the practical application. The large scale physical model tests were carried out to investigate the stress state, failure mode and bearing mechanisms of the lattice beam anchorage. The results show that the fully grouted lattice beam anchorage enhances the stability of the slope. The maximum anchoring force takes place near the sliding surface and descends from the sliding surface to the two ends. The loads to the lattice beam are very small and the foundation pressure distributes as a triangle, with the maximum near the middle and tapering towards both ends. The shear deformation of the anchor arises at the slip surface and the lattice beam bends little. The whole slope slipped. The anchor is the main anti-slide member which plays an anti-shear role and the lattice beam guarantee the overall stability of the slope. The design of the fully grouted lattice beam anchorage should focused on the shear strength of the anchor, and the lattice beam should be the reinforced concrete.