以低碳钢片模拟全长黏结锚杆,开展均质岩质边坡离心模型试验,研究了锚杆的应力响应规律.基于试验模型锚杆应力响应规律启发及实际均质边坡变形破坏演变规律,提出仅针对边坡松弛区进行局部强度折减,数值模拟探讨了均质岩质边坡单锚应力监测的较佳位置.结果表明:均质岩质边坡变形破坏起始于坡脚的剪切破坏,且随着边坡变形破坏的开展,靠近坡脚的全长黏结锚杆会较早产生明显的应力响应,锚杆应力增长速率会不断增加;锚杆应力监测点距离边坡潜在滑动面(塑性变形区)越近,锚杆应力响应时间越早,且量值越大;建议在距离坡脚0.25～0.35H(H为边坡高度)的坡面处布设监测锚杆,但对于具体监测边坡对象,应具体问题具体分析.研究成果可为均质岩质边坡的锚杆监测工作提供一定的参考借鉴.%Using low-carbon steel sheets as fully grouted bolts,centrifugal model test of homogeneous rock slope was carried out and stress responses of fully grouted bolts were studied.Based on the stress responses of fully grouted bolts from the test and practical deformation and failure law of homogeneous rock slope,the preferred position for single bolt stress monitoring of one homogeneous rock slope was also explored by using finite-difference numerical simulation technology and a suggested local strength reduction method on relaxation region.The results are as follows:deformation and failure of the homogeneous rock slope started at the shear failure at the toe of the slope,earlier and obvious stress response of the bolt close to the toe of the slope will be triggered and the stress growth rate of the bolt will also continue to increase with the deformation and failure development of the slope;the closer the distance between stress monitoring point installed in one bolt and potential sliding surface (plastic deformation zone) of the slope,the earlier the time of the bolt stress response and the larger the bolt stress is.It is suggested that the monitoring bolt be put on the slope with 0.25～0.35 H (H is slope height) from the toe of homogeneous rock slope,and concrete analysis must be done for a concrete problem.Results from this paper can provide some references to some extent for the bolts monitoring work of homogeneous rock slope.
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