基于锚索内力增量比指标的边坡安全性预警研究  

Research on Slope Safety Warning Based on Increment Ratio of Anchor Cable Internal Force

作　　者：陈冠琪 郭昭赢 张晓温[2] 李剑[3] 郭建华 陈佳鑫 CHEN Guanqi;GUO Zhaoying;ZHANG Xiaowen;LI Jian;GUO Jianhua;CHEN Jiaxin(Second Engineering Company of China Railway Wth Bureau Group Co.,Ltd.,Shiyan 442000,China;China Railway Siyuan Survey and Design Group Co.Ltd.,Wuhan 430070,China;Chinese Academy of Sciences,Institute of Rock and Soil Mechanics,Wuhan 430071,China;School of Environmental Science and Engineering,Changzhou University,Changzhou 213164,China)

机构地区：[1]中铁十一局集团有限公司第二工程公司,湖北十堰442013 [2]中铁第四勘察设计院集团有限公司,湖北武汉430070 [3]中国科学院武汉岩土力学研究所,湖北武汉430071 [4]常州大学环境科学与工程学院,江苏常州213164

出　　处：《安全与环境工程》2023年第3期145-151,160,共8页Safety and Environmental Engineering

基　　金：国家自然科学基金项目(51579236);国家自然科学基金青年基金项目(41702337);湖北省交通厅科技项目(2016-600-1-1)。

摘　　要：预应力锚索作为主动加固手段,可提高边坡的稳定性。但公路边坡的锚固工程并非永久保障,随着岩土体外部荷载以及内部结构的改变,边坡仍然存在失稳破坏的潜在风险。因此,边坡安全性预警研究对于防灾减灾有着重要意义。以某实际预应力锚索加固边坡工程为例,采用数值仿真方式,通过建立边坡稳定性计算模型,得到不同锚索初始预应力下锚索内力增量与边坡岩土体强度折减系数的关系曲线,并将边坡滑动面起始发育和滑动面贯通分别对应的边坡岩土体强度折减系数λ_(1)、λ_(2)对应的点作为边坡安全性预警点,建立以锚索内力增量比作为边坡安全稳定状态的预警指标,提出了基于锚索内力增量比的边坡安全性预警方法和判别标准,该方法消除了锚索初始预应力的影响,便于工程应用,并得到锚索内力增量比在不同阶段的边坡安全性预警阈值与锚索初始预应力呈现出e指数关系,可用公式y=AeBx表示,实际应用中可根据这一关系式实现不同锚索预应力加固边坡安全稳定状态的预警。Prestressed anchor cables can improve slope stability as an active reinforcement method.However,the anchoring of the slope is not a permanent guarantee.The slope still has the risk of instability and failure due to the change of external load and internal structure of rock and soil.Therefore,the early warning research on slope stability is significant for disaster prevention and mitigation.Taking an actual slope project as an example,the relationship between the internal force increment of anchor cable and the slope strength reduction coefficient under differen t pres tress is obtained by establishing the slope calculation model through numerical simulation.The points corresponding to λ_(1)(strength reduction coefficient at the initial development of slope sliding surface)and λ_(2)(strength reduction coefficient at the penetration of slope sliding surface)are taken as the early warning points of slope safety.The internal force increment ratio of the anchor cable is established as the early warning index to judge the stability state of a slope.The slope safety early warning method and criterion are proposed.This method eliminates the influence of the initial prestress of anchor cable and is convenient for engineering applications.The research also shows that the early warning threshold of the internal force increment ratio of the anchor cable at different stages has an e-index relationship with the initial prestress of the anchor cable.The formula y=A·e^(Bx)can express the relationship,and the early warning of the safety and stability of the slope reinforced by different anchor cables can be realized based on the relationship in practical engineering.

关 键 词：边坡安全性预警 预应力锚索 锚索内力增量比 安全系数 

分 类 号：X4[环境科学与工程—灾害防治] TU43[建筑科学—岩土工程]