基于预应力监测的锚固边坡整体稳定性分析

Overall Stability Analysis of Anchorage Slope Based on Prestress Monitoring

为研究边坡锚索的预应力损失规律及其对边坡整体稳定性的影响,采用智能弦式数码穿心力传感器对多锚加固边坡锚索预应力进行了长期监测,并结合最小耗能原理的塑性极限分析上限法对多锚边坡的整体稳定性进行了分析。研究结果表明:锚索张拉后其预应力均会出现不同程度的损失,作用于每级边坡中上部的锚索其预应力损失程度最大且有明显的波动现象,波动范围为2%~4%,在锚索预应力损失的3个阶段中,快速损失阶段锚索预应力的损失比重最大,约占总损失率的70%~90%;对边坡进行锚索加固虽可以显著提高其整体稳定性,但不应忽略锚索预应力损失的影响;作用于边坡中下部的各锚索是控制边坡整体稳定性的关键,在后期维护中应着重加强边坡中下部各锚索的预应力补偿,以显著提高多锚加固边坡的整体稳定性。

In order to study the prestress loss law of slope anchor cable and its influence on the overall stability of slope,the intelligent string type digital penetrating force sensor is used to monitor the prestress of the anchor cables of the multi-anchor reinforced slope for a long time,and the overall stability of multi-anchor slope is analyzed with the upper limit method of plastic limit analysis based on the principle of minimum energy consumption.The research results show as follows.The prestress of the anchor cable will lose to different degrees after the tension is completed,the prestress loss of anchor cablesacting on the middle and upper part of each stage of slope is the largest and has obvious fluctuation phenomenon,compared with the stable value,the fluctuation range of the prestress of each anchor cable in the middle and upper part of the slope is about 2%~4%.In the three phases of prestress loss of anchor cables,the loss proportion of prestress in rapid loss phase is the largest,accounting for 70%~90%of the total loss;and the prestress of each anchor cable in the middle and lower part of the slope can be considered as no obvious fluctuation.Although the overall stability of slope can be significantly improved by anchor cable reinforcement,the influence of prestress loss of anchor cable should not be ignored,the anchor cable acting on the middle and lower part of and the prestress of each anchor cable inthe middle and lower part of the slope can be considered as no obvious fluctuation.Although the overall stability of slope can be significantly improved by anchor cable reinforcement,the influence of prestress loss of anchor cable should not be ignored,the anchor cable acting on the middle and lower part of the slope is the key to control the overall stability of the slope.In the later maintenance,the prestress compensation of each anchor cable in the middle and lower part of the slope should be strengthened to significantly improve the overall stability of the slope reinforced by multiple anchors.