摘要
川藏铁路沿线岩体受地质构造、风化作用以及酸雨作用的影响,广泛发育有深厚的碎裂带,工程开挖常形成长大碎裂岩质边坡。该类边坡除坡面碎块石的崩落外,还存在整体失稳风险,常规主动网难以有效加固。基于此,提出锚墩式主动网新型组合结构,以预应力锚索代替主动网中的短锚杆,约束碎裂岩质边坡坡面岩块位移的同时进行边坡的深层加固。设计了1︰10大比例尺室内模型试验,探究强降雨条件下锚墩式主动网在碎裂岩质边坡加固中的应力-应变特征,探索其协同受力机理及设计方法。试验结果表明,强降雨条件下,锚墩式主动网组合结构可协同受力,且主动网受力对预应力锚索的工作状态有显著影响,会形成明显的二次张拉,设计时应充分考虑。
Under the comprehensive influences of tectonics,weathering,and acidification of acid rain,the rock mass along the Sichuan-Tibet Railway has extensive deep shattered zones.When the rock masses are excavated due to constructions,a series of deep and cataclastic rock slopes can be formed.These slopes are highly susceptible to collapse as well as overall instability,which is hard to be reinforced by the traditional safety netting system(SNS).This study proposes a new composite structure for slope protection,anchored flexible system,replacing bolts of SNS with prestressed anchor cables to constrain the surface displacement of the cataclastic rock slope while simultaneously stabilizing the slope body.Here,we conduct 1︰10 large-scale indoor model tests to explore the stress-strain characteristics,the coordinated loading mechanism,and the design method of the anchored flexible systems for cataclastic rock slope protection under heavy rainfall conditions.Model test reveals the coordinated loading between both prestressed anchor cables and nets in anchored flexible systems when the cataclastic rock slope deformation happens.The stress of the flexible nets has significant impacts on the working state of the prestressed anchor cable,and it can form an obvious re-tension,which should be fully taken into account in the design.
作者
赵晓彦
肖典
罗改
罗天成
吴兵
ZHAO Xiaoyan;XIAO Dian;LUO Gai;LUO Tiancheng;WU Bing(Department of Geology Engineering,Southwest Jiaotong University,Chengdu 611756,China;Evaluation and Utilization of Strategic Rare Metals and Rare Earth Resource Key Laboratory of Sichuan Province,Sichuan Geological Survey,Chengdu 610081,China;Sichuan Communication Surveying&Design Institute Co.,Ltd.,Chengdu 610017,China)
出处
《工程地质学报》
CSCD
北大核心
2021年第2期365-374,共10页
Journal of Engineering Geology
基金
国家自然科学基金资助项目(资助号:41672295)
中国铁路总公司科技研究开发计划系统性重大项目(资助号:P2018G047)。
关键词
碎裂岩质边坡
锚墩式主动网
新型组合结构
加固机理
模型试验
Cataclastic rock slope
Anchored active net
New composite structure
Reinforcement mechanism
Model test
