动荷载下玄武岩纤维喷射混凝土破坏与拉伸规律研究  

Study on the Damage and Tensile Law of Basalt Fiber Sprayed Concrete under Dynamic Load

作　　者：郭俊波 王堃 梁君 章欣宇 裴广朝 李雄姿 肖定军[3] GUO Junbo;WANG Kun;LIANG Jun;ZHANG Xinyu;PEI Guangchao;LI Xiongzi;XIAO Dingjun(China Anneng Group Third Engineering Bureau Co.,Ltd.;Jiulong County Yalong River Mining Co.,Ltd.;School of Environment and Resource,Southwest University of Science and Technology)

机构地区：[1]中国安能集团第三工程局有限公司,四川省成都市610000 [2]九龙县雅砻江矿业有限责任公司,四川省甘孜藏族自治州626799 [3]西南科技大学环境与资源学院

出　　处：《现代矿业》2025年第2期137-144,共8页Modern Mining

摘　　要：为了探究冻融环境下,玄武岩纤维喷射混凝土(Basalt Fiber sprayed concrete,BFSC)受平常动荷载作用的动态破坏特征,利用快速冻融试验机,模拟了玄武岩纤维喷射混凝土冻融循环0,10,20,30次的作用环境,采用分离式霍普金森压杆(split Hopkinson pressure bar,SHPB)对BFSC平台巴西圆盘试件进行动态劈裂试验。使用不同等级的分级筛,运用分形及能量耗散理论,研究破碎块度分布规律、分形特征及能量耗散规律。结果表明,不同冻融循环次数后,玄武岩纤维喷射混凝土破坏形式沿径向对称,贴近入射杆端出现三角形破碎区。增加冻融循环次数与提高应变率均会造成碎块的平均粒径减小、分形维数增大;随着冻融循环次数的增加,试样结构损伤和力学性能劣化加剧,动态抗拉强度降低;同一冻融循环次数下,动态抗拉强度具有明显的应变率增强效应。此外,引入平均入射能变化率对能量特性进行详细分析,当冻融循环次数为30、入射能平均变化率为0.47 MJ/s时,玄武岩纤维喷射混凝土动态拉伸过程中的耗散能与0次相比降低幅度最大,为32.41%。In order to investigate the dynamic failure characteristics of Basalt Fiber Sprayed Concrete(BFSC)under dynamic loading in a freeze-thaw environment,a rapid freeze-thaw test machine was used to simulate the freeze-thaw environments of 0,10,20,and 30 cycles for BFSC.A split Hopkinson pressure bar(SHPB)was employed to conduct dynamic Brazilian splitting tests on BFSC platform Brazilian disc specimens.By using different levels of classification screens and applying fractal theory and energy dissipa-tion theory,the distribution law of fragment size,fractal characteristics of fragment size,and energy dissipa-tion law were studied.The results indicate that after different freeze-thaw cycles,the failure mode of basalt fiber shotcrete is radially symmetrical,with a"triangular"fracture zone appearing near the end of the inci-dent rod.The increase in the number of freeze-thaw cycles and the rise in strain rate will both cause the aver-age particle size of the fragments to decrease and the fractal dimension to increase.As the number of freeze-thaw cycles increases,the structural damage and deterioration of the mechanical properties of the samples intensify,and the dynamic tensile strength decreases.Under the same number of freeze-thaw cycles,the dy-namic tensile strength exhibits a significant strain rate enhancement effect.Furthermore,a detailed analysis of energy characteristics was conducted by introducing the average incident energy variation rate.It was found that when the number of freeze-thaw cycles is 30 and the average incident energy variation rate is 0.47 MJ/s,the dissipated energy during the dynamic tensile process of basalt fiber sprayed concrete decreases by the largest margin of 32.41%compared to 0 cycles.

关 键 词：玄武岩纤维喷射混凝土 冻融循环 劈裂抗拉强度 耗能特征 

分 类 号：TU528[建筑科学—建筑技术科学]