Failure of transversely isotropic rock under Brazilian test conditions
Failure of transversely isotropic rock under Brazilian test conditions
复制标题
DOI：
10.1016/j.ijrmms.2014.04.006
复制
发表时间：
2014-09
影响因子：
7.2
通讯作者：
A. Vervoort;K. Min;H. Konietzky;Jung-Woo Cho;B. Debecker;Quoc-Dan Dinh;T. Frühwirt;A. Tavallali-A.-Tavallal
中科院分区：
文献类型：
--
作者：
A. Vervoort;K. Min;H. Konietzky;Jung-Woo Cho;B. Debecker;Quoc-Dan Dinh;T. Frühwirt;A. Tavallali-A.-Tavallal
在巴西试验条件下，研究了9种不同岩石（2种砂岩、1种页岩、2种板岩、1种片岩和3种片麻岩）的横向各向同性岩石材料的行为。研究了强度变化和试验引起的最终断裂模式随弱面倾角的变化规律。这两个参数的观测结果的结合清楚地说明了这类岩石破坏的复杂性，这可以通过假设四种不同的趋势来总结。强度随倾角变化的四种趋势范围从很少或没有变化（趋势1，即强度的各向同性行为）到从很小的角度开始强度急剧下降，然后趋于平稳（趋势4）。趋势2的特征是在0°到45°之间保持恒定值，然后线性减小，而趋势3对应于整个区间的强度减小，但相当系统地减小，近似线性变化。在这四种趋势中，沿弱面和任何其他方向的各自裂缝的相对长度都有不同的变化。对于所研究的岩石，在弱面以外的方向上存在优势裂缝向沿弱面方向的优势裂缝的交叉。对于这四种趋势，这个交叉点的位置有系统的变化，即，平均而言，趋势1的倾角约为75°，趋势4的倾角约为15°。当倾角大于交叉点时，岩石试样的破坏主要是由于两条加载线之间的分裂。
The behavior of transversely isotropic rock material was studied under Brazilian test conditions for nine different rocks (two sandstones, one shale, two slates, one schist, and three gneiss). Both the variation of the strength and the final fracture patterns induced by testing were examined as a function of the inclination angle of the weak planes. The combination of the observations for both parameters illustrated clearly the complexity of the failure of such rocks, which was summarized by assuming four different trends. The four trends for the variation of the strength as a function of the inclination angles range from little or no variation (trend 1, i.e., isotropic behavior for strength) to a sharp decrease of the strength from very small angles onwards, followed by a leveling off (trend 4). Trend 2 is characterized by a constant value between 0° and about 45°, followed by a linear decrease, while trend 3 corresponds to a decrease of the strength over the entire interval, but a rather systematic decrease, approximating a linear variation. Different variations were observed among these four trends in terms of the relative lengths of the respective fractures along the weak planes and in any other direction. For the rocks investigated, there is a cross-over from dominant fractures in directions other than the weak planes to dominant fractures along the weak planes. For the four trends, there are systematic changes in the position of this cross-over point, i.e., on average, at about an inclination angle of 75° for trend 1 and at about 15° for trend 4. For inclination angles larger than the cross-over point, the rock specimens failed primarily by splitting between both loading lines.