锚索力学性能测试与分析

Tests and analysis on mechanical properties for cable bolts

为了得到不同锚索的力学性能参数,基于实验室进行的4种常用锚索钢绞线的拉伸试验和5组锚索托板的压缩试验,可将钢绞线拉伸载荷-位移曲线可分为4个阶段:初始承载阶段、弹性变形至屈服阶段、屈服后强化阶段、破断阶段。钢绞线弹性范围内的位移很小,其延伸主要发生在屈服之后,且随着钢绞线直径增加有增大的趋势。5组锚索托板承载力明显大于钢绞线承载力。托板压缩载荷-位移曲线可分为5个阶段:托板拱部形状与尺寸、底面平整度是影响托板承载力的主要因素;托板在不同承载阶段压缩变形量有显著差别;底面不平整、呈弓形的托板各阶段压缩量较大;球形垫圈发生显著缩颈变形,并逐步压入托板球窝也影响托板整体变形性能。

In order to obtain mechanical feature parameters of different anchor cables,based on tensile tests for four types of cable strands and compressive tests for five groups of cable plates were carried out in laboratory. The tensile load-displacement curve of the strands can be classified as four stages: initial loading stage; elastic deformation to yield stage; strengthening stage after yield; broken stage. The strand displacement in elastic limit is pretty small,while the strand elongation appears mainly after yield,and it gradually increases with the strand diameter. The bearing capacity of five groups of cable plates is obviously higher than that of the cable strands. The compressive load-displacement curve of the cable plates can be classified as five stages. The arch shape,size and bottom smoothness of plate are the main factors affecting its bearing capacity. There exist obvious differences on plate compressive deformation during various compressive stages. The plates with uneven bottom usually have larger compressive deformation. The domed washer is often pressed to occur necking deformation,and squeezed into the plate socket,which also affects the deformability of the plate.