三轴分级循环加卸载下爆破损伤顶板砂岩能量耗散试验研究  

Blast damage to sandstone of top slab under triaxial graded cyclic loading and an unloading experimental study on energy dissipation

作　　者：王梦想[1] 王浩 马守龙[1,2] 宗琦 汪海波[1] 徐颖[1] WANG Mengxiang;WANG Hao;MA Shoulong;ZONG Qi;WANG Haibo;XU Ying(School of Civil Engineering and Architecture,Anhui University of Science and Technology,Huainan 232001,China;China Coal Xinji Energy Co.,Ltd.,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]中煤新集能源股份有限公司,安徽淮南232001

出　　处：《振动与冲击》2024年第16期227-237,共11页Journal of Vibration and Shock

基　　金：安徽省高等学校自然科学基金(2022AH050841);国家自然科学基金(52274071,52074009)。

摘　　要：为探究不同围压环境爆破荷载损伤砂岩在循环加卸载作用下能量耗散演化规律,利用三轴试验加载装置系统对三种不同损伤度的砂岩试件开展不同围压下的分级循环加卸载试验,并结合电子数码显微镜获取不同损伤度试件细观结构,分析爆破荷载损伤、围压及加载级数对试件能量耗散及破裂破碎形态的影响规律。结果表明:(1)爆破荷载作用会对岩体造成损伤,单轴压缩荷载下振动损伤、爆破损伤试件峰值强度降幅分别为5.53%、18.87%,单轴分级循环加卸载作用对未损伤、振动损伤试件产生劣化,对爆破损伤试件产生强化作用;(2)爆源近端岩体损伤程度较高,在外荷载作用下率先发生破坏,围压的存在显著降低试件的破裂破碎程度,试件呈剪切、拉伸及压碎破坏多种模式共存;(3)循环加卸载过程中第1次循环加载试件所获取总能量及塑性变形能最大,循环次数的增加使试件塑性变形能及耗散能整体均呈现减小趋势,围压及循环加载级数的增大使试件在循环加载过程中各能量均随之增加;(4)分级循环加卸载过程中Ⅱ级循环加卸载试件耗能比要低于Ⅰ级与Ⅲ级,爆破损伤、振动损伤及未损伤试件在Ⅰ级、Ⅱ级、Ⅲ级循环加卸载过程中耗能比均值分别为15.73%、12.47%、13.95%,13.49%、12.44%、13.46%,12.07%、8.69%、11.56%,爆破荷载损伤改变岩体内部结构使得试件在循环加卸载作用下耗能占比更加显著。In order to investigate the evolution of energy dissipation under cyclic loading and unloading of sandstone damaged by blasting load in different circumferential pressure environments,graded cyclic loading and unloading tests were carried out on three sandstone specimens with different damage degrees under different circumferential pressures by using a triaxial test loading device system,and the fine structure of the specimens with different damage degrees was obtained by combining with electronic digital microscopy.The effects of blasting load damage,confining pressure and loading series on energy dissipation and fracture morphology are analyzed.The results show that:1)The blasting load action will cause damage to the rock body,the peak strength reduction of vibration damage and blasting damage specimens under uniaxial compression load is 5.53%and 18.87%respectively.The uniaxial graded cyclic loading and unloading degrades the undamaged and vibration-damaged specimens,and strengthens the blasting damage specimens.2)The extent of damage to the proximal end of the detonation cord is higher,the first damage occurs under the action of external loading,the existence of the surrounding pressure significantly reduces the degree of rupture and fragmentation of the specimen,the specimen is shear,tensile and crushing damage multiple modes coexist.3)In the process of cyclic loading and unloading,the total energy and plastic deformation energy obtained by the specimen reached the maximum at the first cyclic loading,and the plastic deformation energy and dissipated energy of the specimen showed a decreasing trend as the number of cycles increased.The increase of the circumferential pressure and the number of cyclic loading stages makes the specimen increase in each energy during the cyclic loading process.4)The energy consumption ratio ofⅡ-level cyclic loading and unloading specimens is lower than that ofⅢ-level andⅠ-level in the process of graded cyclic loading and unloading.Blast damage,vibration damage and undamaged

关 键 词：爆破损伤 顶板砂岩 分级循环加卸载 峰值强度 破裂破碎形态 能量耗散 耗能比 

分 类 号：TU45[建筑科学—岩土工程]