摘要
锚杆支护是一种加固边坡的有效方式,但目前针对复杂多层岩质边坡的锚杆最优锚固角研究较少,且未考虑中间主应力对锚固效果的影响。采用统一强度理论,以全长粘结型锚杆为对象,根据锚杆失效模式及锚固段与围岩的作用方式,推导出复合多层岩体中锚杆的极限抗拔力公式。通过计算不同岩层锚固段微元体的单位长度抗力比,提出了复合多层顺倾岩质边坡的锚杆最优锚固角模型与最优锚固角的确定方法。将该方法应用到三峡库区巴东县一公路边坡工程,结果表明模型计算所得最优锚固角与均匀试验方案确定的最优锚固角一致。新方法计算所得的边坡单位宽度锚杆总长与规范法计算结果相比减少约11.2%,与传统莫尔-库伦理论计算结果相比减少约8.9%。研究结果可为复合多层顺倾岩质边坡的锚固支护设计提供一定的参考和借鉴。
Anchor bolt support is an effective way to reinforce slopes,but there is little research on the optimal anchor angle of the bolt for the composite multi-layer rock slope at present,and the influence of the intermediate principal stress on the anchoring effect is not considered.Based on the unified strength theory,taking the full length bonded bolt as the object,according to the general failure form of the bolt and the interaction mode between the bolt anchorage section and the surrounding rock,we derive the formula of the ultimate pullout resistance of bolts in the composite multi-layer rock mass.By calculating the resistance ratio per unit length of the micro element in the anchorage section of different rock strata,we put forward a model of the optimal anchorage angle and the determination method of optimal anchorage angle for the composite multi-layer inclined rock slopes.The method is applied to the Badong County highway slope in the Three Gorges Reservoir area.The results show that the optimal anchorage angle calculated by the model is consistent with that determined by the uniform experimental scheme.Compared with the standard method and the method based on traditional Mohr Coulomb theory,the total anchorage length per unit width calculated by the model is reduced by about 11.2%and 8.9%,respectively.The research results can provide a reference for the design of anchorage support of composite multi-layered inclined rock slope.
作者
冼进业
陈建林
李长冬
冼树兴
王妍
XIAN Jinye;CHEN Jianlin;LI Changdong;XIAN Shuxing;WANG Yan(Faculty of Engineering,China University of Geosciences,Wuhan 430074,China;PowerChina Huadong Engineering Corporation Limited,Hangzhou 311100,China;Hubei Badong Geological Disaster National Field Scientific Observation and Research Station,China University of Geosciences,Wuhan 430074,China)
出处
《人民长江》
北大核心
2023年第10期221-227,242,共8页
Yangtze River
基金
国家自然科学基金优秀青年科学基金项目(41922055)
国家自然科学基金重点基金项目(41931295)
中国长江三峡集团有限公司科研项目(2019073)。
关键词
复合多层岩质边坡
锚固优化设计
锚固角
统一强度理论
锚杆长度
composite multi-layer rock slope
anchorage optimization design
anchorage angle
unified strength theory
anchor bolt length
