摘要
深部地层高地温、高地应力环境使巷道围岩树脂锚固支护结构稳定性降低,围岩变形有效控制问题亟待解决。因此,研究温度与压力耦合作用下锚杆杆体-树脂锚固剂界面变形破坏机理十分必要。首先,根据两淮矿区深部支护工程现状并结合室内不同温度环境下拉拔试验结果,发现高地温环境下树脂锚固体变形破坏加剧;进一步分析锚固体受拉拔荷载作用轴向、径向破坏模式,将第一锚固界面破坏分为弹性围岩-剪切-滑移型、未贯穿-剪胀滑移破坏及贯穿-剪胀滑移破坏等3种模式。其次,基于弹塑力学分析受围岩应力作用锚固界面不同破坏类型的界面受力状态,考虑高温环境下树脂锚固剂层力学强度弱化,建立温度-围岩应力耦合作用的第一界面失效破坏力学计算模型;分析围岩应力、环境温度及弹性模量比等因素变化对第一界面锚固性能影响的规律,发现第一界面极限轴向荷载随温度升高而降低,围岩处于裂隙发育或裂隙贯穿状态时,围岩应力对第一锚固界面剪切破坏影响程度较未产生裂隙时大幅度增高。最后,结合室内拉拔试验数据对比验证所推导计算方程式的合理性。研究可为深部巷道围岩稳定性控制及锚固支护参数设计提供理论依据。
In mining,the high temperatures and stresses in deep strata decrease the stability of the rock that surrounds the resin-anchor support structures of roadways,and so a solution is urgently required regarding how to exert effective control over the deformation of such rock.Therefore,it is necessary to study the mechanism for deformation and failure of the interface between the bolt body and the resin anchoring agent under the coupled effect of temperature and pressure.First,a description is given of the current situation regarding deep support engineering in the Lianghuai mining area,and combined with the results of pull-down tests in different indoor temperature environments,it is concluded that the deformation and damage of resin anchors are aggravated by high temperatures.Next,the axial and radial failure modes of the anchor body under pull-out load are analyzed,and the failure of the first anchorage interface is divided into three modes,i.e.,elastic shear slip failure of the surrounding rock,non-penetration shear expansion slip failure,and penetration shear expansion slip failure.Based on elastic-plastic analysis of the stress state of the interface with different failure types of the anchoring interface under the stress of the surrounding rock,and considering the weakening of the mechanical strength of the resin anchoring layer under high temperatures,a calculation model is established for the failure mechanics of the first interface under the coupled effect of the temperature and stress of the surrounding rock.How changes in the surroundingrock stress,ambient temperature,elastic modulus ratio,and other factors influence the anchorage performance of the first interface is analyzed,and it is concluded that the ultimate axial load of the first interface decreases with increasing temperature.When fissures are either developing in or penetrating the surrounding rock,the influence of its stress on the shear failure of the first anchorage interface is significantly higher than that when there are no fissures.Finally,the proposed calculation model is shown to be effective by comparing its predictions with the results of indoor drawing tests.The present research provides a theoretical basis for controlling the stability of surrounding rock and designing anchor-support parameters for deep roadways.
作者
刘小虎
姚直书
程桦
查文华
LIU Xiaohu;YAO Zhishu;CHENG Hua;ZHA Wenhua(School of Architecture and Civil Eng.,Anhui Univ.of Sci.and Technol.,Huainan 232000,China;Research Center of Mine Underground Eng.of Ministry of Education,Anhui Univ.of Sci.and Technol.,Huainan 232001,China;School of Civil and Architectural Eng.,East China Univ.of Technol.,Nanchang 330013,China)
出处
《工程科学与技术》
EI
CAS
CSCD
北大核心
2024年第4期108-119,共12页
Advanced Engineering Sciences
基金
安徽高校自然科学研究项目(2022AH050814)
安徽理工大学引进人才基金(13210028)
安徽理工大学校级重点项目(xjzd2020-17)
淮南市科技计划项目(2021071)
国家自然科学基金项目(51964002
52174104)。
关键词
温度-压力耦合
树脂锚固体
锚固界面
失效机理
因素分析
temperature and pressure coupling
resin anchor
anchoring interface
failure mechanism
factor analysis
作者简介
刘小虎(1986-),男,讲师.研究方向:岩土工程,巷道支护.E-mail:2020134@aust.edu.cn。
