格构锚固体系承载机理及破坏模式的试验研究

通过开展格构锚固体系与滑坡体相互作用的室内物理模型试验，测得格构锚固体系的梁下土体抗力、格梁内力、位移及变形破坏等关键数据，进而得出滑坡防治中格构锚固体系的承载机理与破坏模式。结果表明在滑坡推力及锚索锚固力作用下，格梁节点处下部受拉、上部受压，跨中处下部受压、上部受拉，整体受力呈“S”曲线状;随着荷载的增加，格梁节点处向坡内弯曲变形、跨中处向坡外弯曲变形;格梁的主要破坏形式有跨中“弓”形弯折破坏、节点处受压碎裂破坏、格梁中间土体拱出破坏、格梁上方土体挤出破坏4种类型;格梁的主要破坏模式为塑性多绞弯折破坏。

Model Test on Mechanical Properties and Failure Mode of Lattice Framed Anchor System

The mechanical properties and failure modes of lattice framed anchor system in preventing landslide are investigated through large-scale physical model test on the interaction between anchor system and landslide.The resistance of soil under lattice girder,the internal forces,displacements and deformations of lattice girder are obtained.Results show that under the actions of landslide thrust and anchorage force,the lattice girder as a whole is subjected to forces in an "S" shape,which means that the beam part below node was subjected to tension,the above node compression,and below mid-span of the beam compression,and above mid-span tension;with the increase of load and the gradual destruction of landslide model,the node of lattice girder bends towards the inside of the slope,the mid-span bends towards the outside.Moreover,the failure modes of lattice framed anchor system are summarized into four types:bending failure in an "S" shape in the mid-span,cataclastic failure of node caused by compression,extrusion of soil between girders,and extrusion of soil above girders,among which plastic bending failure is a main failure mode.