摘要
爆破能量瞬态释放条件下岩石损伤机制是爆破工程和地下空间工程的研究焦点。通过开展现场爆破试验,对能量释放前、后岩石进行纵波波速、孔隙率、电阻率和抗拉强度试验以及微观结构分析,揭示了能量释放条件下场地蚀变闪长玢岩损伤特征与范围,而后通过引入宏观尺度孔隙率和微观尺度微裂隙密度的变化为基础建立损伤变量,对试样损伤机制进行了定性和定量联合分析。结果表明:BZ2、BZ3和BZ4随孔深的增大蚀变闪长玢岩宏观指标变化程度均不断减小且呈现出明显的一致性阶梯状变化特征,同一孔深处指标变化程度由大到小依次为BZ2、BZ3、BZ4,依据宏观指标变化综合判定BZ2、BZ3和BZ4岩石损伤深度分别为5.72 m、3.71 m和2.85 m;爆破作用下试样裂隙、孔洞等缺陷发育程度、连通性的差异性改变是导致岩石试样呈现差异性损伤的根本原因;宏观、微观损伤变量与宏观损伤特征之间存在显著的量化线性对应关系,可以作为判定爆破能量瞬态释放条件下岩石损伤范围与程度的量化指标。
The damage mechanism of rock under transient energy caused by blasting is the research focus of blasting and underground space engineering.The research conducted field blasting experiments,and ultrasonic wave velocity,porosity,resistivity,and tensile strength tests as well as scanning electron microscope(SEM)inspections of rocks after blasting were carried out.By comparing them to rocks not affected by blasting,the blasting damage characteristics and range of rocks were identified.Then,the damage variables based on the change of macro porosity and micro-crack density were established,and the damage mechanism of the samples was analyzed qualitatively and quantitatively.The results show that the degree of change in the macroscopic test indicators of the altered diorite porphyrite at BZ2,BZ3,and BZ4 decreases continuously with increasing depth,presenting distinct characteristics of consistent stepwise change.The sequence of variation degree is BZ2,BZ3,and BZ4.Based on the change of the macro indicators,it is comprehensively analyzed that the damage depths of the rocks at BZ2,BZ3,and BZ4 are 5.72 m,3.71 m,and 2.85 m,respectively.The underlying cause of the difference in rock damage degree is the differential change in the development degree and connectivity of micro-defects such as cracks and pores due to blasting.There is a significant quantitative linear correlation between macro and micro damage variables and macro damage characteristics.Therefore,they can be used as quantitative indices to reveal the range and degree of rock damage caused by blasting.
作者
崔凯
焦堂贤
王启睿
吴国鹏
马俊宁
CUI Kai;JIAO Tangxian;WANG Qirui;WU Guopeng;MA Junning(Western Center of Disaster Mitigation in Civil Engineering,Ministry of Education,Lanzhou University of Technology,Lanzhou 730050,China;Department of Civil Engineering,Tsinghua University,Beijing 100084,China)
出处
《工程地质学报》
北大核心
2025年第4期1332-1342,共11页
Journal of Engineering Geology
基金
国家自然科学基金项目(资助号:42107206)
甘肃省自然科学基金项目(资助号:22JR5RA292)。
关键词
能量
瞬态释放
蚀变闪长玢岩
损伤特征
损伤变量
Energy
Transient release
Altered diorite porphyrite
Damage characteristics
Damage variables
