An Experimental Investigation of the Influence of Loading Rate on Rock Tensile Strength and Split Fracture Surface Morphology
An Experimental Investigation of the Influence of Loading Rate on Rock Tensile Strength and Split Fracture Surface Morphology
复制标题
加载速率对岩石抗拉强度及劈裂断口形貌影响的试验研究
DOI：
10.1007/s00603-021-02368-4
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发表时间：
2021-02-03
影响因子：
6.2
通讯作者：
Maochu, Zhang
中科院分区：
文献类型：
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作者：
Cui, Zhen;Qian, Sheng;Maochu, Zhang
为了研究加载速率对岩石材料抗拉强度和劈裂断口形貌的影响，采集了花岗岩、玄武岩和石灰岩3种岩石试件，在不同加载速率下进行了巴西试验。测定了岩石材料的抗拉强度，研究了加载速率对岩石材料抗拉强度的影响。利用光学三维扫描技术获得了劈裂断裂面的数字地形图模型，研究了加载速率对断裂面几何形貌的影响。通过计算三种岩石断裂面的粗糙度指数，定量研究了加载速率和抗拉强度对粗糙度的影响。研究结果表明，岩石抗拉强度随加载速率的增大而增大。在双对数坐标系下建立了拉伸强度与加载速率之间的线性关系。四个不同的粗糙度指数被用来描述分裂断裂表面的形态。分析结果表明，各粗糙度指数的大小均随加载速率的增大而增大。此外，所有三种类型的岩石的粗糙度指数与抗拉强度线性增加。这种线性趋势表明，它是可能的，利用断裂面粗糙度指数来估计岩石抗拉强度。本研究为进一步研究岩石裂隙形态指标与岩石力学参数之间的关系提供了依据。
To investigate the effect of the loading rate on the tensile strength of rock material and the morphology of the resulting split fracture surfaces, three types of rock specimens, namely, granite, basalt and limestone, were collected and tested with Brazilian testing under different loading rates. The tensile strength was measured, and the effect of the loading rate on the tensile strength of the rock material was studied. Digital terrain map models of the split fracture surface were obtained with an optical 3D scanning technique, and the effects of the loading rate on the geometry and morphology of the fracture surface were studied. The influence of the loading rate and tensile strength on the roughness was studied quantitatively by calculating the roughness indices of a fracture surface for all three kinds of rock. The research results show that the rock tensile strength increases with the loading rate. A linear relationship was established in double-logarithmic coordinates to describe the relationship between the tensile strength and the loading rate. Four different roughness indices were used to describe the morphology of the split fracture surface. The analysis results show that the magnitudes of all the roughness indices increase with the loading rate. Additionally, the roughness indices for all three types of rock linearly increase with the tensile strength. This linear trend indicates that it is possible to utilize fracture surface roughness indices to estimate rock tensile strength. The current study may motivate further research on the relationship between the morphology indices of rock fractures and mechanical parameters of the rock.