加载速率对青砂岩抗拉特性及断裂能耗的影响  

The influence of loading rate on the tensile properties and fracture energy consumption of Green sandstone

作　　者：赵环帅 潘永泰 乔鑫 王星宇 毕研琨 余超 曹行健 ZHAO Huanshuai;PAN Yongtai;QIAO Xin;WANG Xingyu;BI Yankun;YU Chao;CAO Xingjian(Shcool of Chemistry and Environmental Engineering/Engineering Research Center for Mining and Urban Solid Waste Recycling,China University of Mining and Technology,Beijing 100083,China)

机构地区：[1]中国矿业大学化学与环境工程学院/矿山与城市固废资源化工程研究中心,北京100083

出　　处：《中山大学学报(自然科学版)(中英文)》2025年第2期120-128,共9页Acta Scientiarum Naturalium Universitatis Sunyatseni

基　　金：国家自然科学基金(52074308)。

摘　　要：结合室内试验与细观参数标定,建立了青砂岩宏-细观力学关系,分析了青砂岩在不同加载速率下的力学特性、裂纹演化规律与能量利用效率。结果表明:(1)加载速率小于0.1 m/s时,青砂岩应力-应变曲线形态基本一致,无明显的差异性;且加载速率越小,脆性破坏越显著。拉力链是导致裂纹扩展与延伸的主导原因,而最终断裂是压力和拉力链相互作用的结果。(2)青砂岩破裂形态可分主裂纹为主、次生裂纹出现、次生裂纹贯穿的破坏形式。随着加载速率的增加,青砂岩裂纹数量与破裂微元数量基本上呈现出相似趋势。(3)加载速率为0.000 5~0.1 m/s,输入能-断裂能曲线呈现上下波动现象,但波动范围较小;在加载速率为0.5~1 m/s时,输入能呈直线增加趋势,断裂能呈先快速增加后变缓的趋势,能量利用效率主要集中于10.262%~11.511%。The macro-micro mechanical relationship of Green sandstone was established by indoor experiments and microscopic parameter calibration.The mechanical properties,crack evolution law,and energy utilization efficiency under different loading rates were analysed.The results showed that:(1)When the loading rate is less than 0.1 m/s,the stress-strain curve shape of the Green sandstone is basically consistent,and the smaller the loading rate,the more significant the Brittle failure.The tension chain is the main cause of crack propagation and extension,and the ultimate fracture is the result of the interaction between pressure and tension chains.(2)The fracture morphology of green sandstone can be divided into the failure way dominated by the main crack,the failure way where secondary cracks appear,and the failure way where secondary cracks penetrate.With the increase of loading rate,the number of cracks and the number of fracture elements in Green sandstone show a similar trend.(3)The loading rate is 0.0005~0.1 m/s,and the input energy fracture energy curve shows up and down fluctuations,but the fluctuation range is small;When the loading rate is 0.5~1 m/s,the input energy shows a nearly linear increase trend,the fracture energy shows a rapid increase,and then a slow trend.The energy utilization efficiency is mainly concentrated in 10.262%~11.511%.

关 键 词：青砂岩 加载速率 巴西劈裂 抗拉特性 断裂能 

分 类 号：TU452[建筑科学—岩土工程]