不同界面倾角岩石-混凝土组合体蠕变特性研究  

Creep behavior of combined rock⁃concrete specimens with different interface inclination angles

作　　者：姚韦靖 刘宇 庞建勇[1,3] 韩金秀 肖宇辰 YAO Weijing;LIU Yu;PANG Jianyong;HAN Jinxiu;XIAO Yuchen(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China;Postdoctoral Science Research Workstation,Wuhu Surveying and Mapping Design Institute Co.,Ltd.,Wuhu 241000,China;Anhui Key Laboratory of Mining Construction Engineering,Anhui University of Science and Technology,Huainan 232001,China)

机构地区：[1]安徽理工大学土木建筑学院,安徽淮南232001 [2]芜湖市勘察测绘设计研究院有限责任公司博士后科研工作站,安徽芜湖241000 [3]安徽理工大学矿山建设工程安徽省高校重点实验室,安徽淮南232001

出　　处：《采矿与岩层控制工程学报》2024年第4期137-149,共13页Journal of Mining and Strata Control Engineering

基　　金：国家自然科学基金资助项目(52174141);淮南市科技计划资助项目(2023A313);矿山建设工程安徽省高校重点实验室开放基金资助项目(GXZDSYS2022106);安徽省大学生创新创业训练计划资助项目(S202310361232)

摘　　要：为探究岩石-混凝土界面对地下建筑支护结构失效的影响,通过7种不同界面倾角的岩石-混凝土组合体试件的单轴和分级加载蠕变试验,研究了其蠕变特性。研究结果表明:随界面倾角的增大,组合体抗压强度呈“W”形变化,倾角在0°,45°,90°时出现极大值,而倾角在30°,60°~75°时出现极小值;并将其破坏模式分为轴向破坏、组合破坏、界面破坏等3种典型破坏模式。组合体蠕变破坏强度低于单轴抗压强度,表明长期加载对组合体会造成损伤;瞬时应变随界面倾角的增大,先减小后增大;与倾角0°的相比,倾角45°,60°,75°,90°的瞬时应变分别减少了22.68%,47.72%,52.01%,4.56%;蠕变比随应力水平的提高呈下降-稳定-上升3个阶段特征;随界面倾角的增大,蠕变破坏临界应力逐渐减小,蠕变稳定阶段逐渐缩短,组合体稳定性逐渐降低。基于试验结果对Burgers蠕变模型参数进行辨识,所得理论曲线与瞬时变形和衰减蠕变阶段试验数据吻合较好。研究成果可为深入认识混凝土支护与围岩结构界面倾角引起的蠕变破坏机制及地下建筑结构支护安全提供参考。The weak rock⁃concrete interface has a significant influence on the underground supporting structure.Seven combined rock⁃concrete specimens with different inclination angles were prepared,and uniaxial and graded loading creep tests were conducted.The results show that the compressive strength of the combined specimens shows W⁃typed fluctuation with the increase of the interface inclination angle.The compressive strength is the largest when the interface inclination angles are 0°,45°,and 90°,and is smallest when the interface inclination angle belongs to 30°and 60°-75°.The failure modes can be categorized into three types:axial damage,combined damage,and interface damage.The creep damage strength of most specimens is lower than the uniaxial compressive strength,which indicates that the specimen is damaged caused by long⁃term loading.The instantaneous strain decreased and then increased with the increase of interface inclination angle.Compared with an interface inclination angle of 0°,the interface inclination angle of 45°,60°,75°,and 90°of specimens instantaneous strain reduced by 22.68%,47.72%,52.01%,4.56%,respectively.The creep ratio shows a decline⁃stability⁃rise three⁃stage behavior with increased stress levels.The critical stress at creep failure decreases with the increase of the interface inclination angle,and the creep stability stage is gradually shortened.With the increase of the interface inclination angle,the stability of specimens gradually decreases.The Burgers creep model parameters were calculated from experiment,and the obtained theoretical curve was in a good agreement with the test data of instantaneous deformation and decay creep stages.The research findings can provide a reference for understanding the creep failure mechanism induced by the interface angle between concrete support and surrounding rock structures and for the safety of underground structural support.

关 键 词：岩石-混凝土组合体 界面倾角 应力水平 蠕变 BURGERS模型 

分 类 号：TU528[建筑科学—建筑技术科学] TU45