Compression-Induced Tensile Mechanical Behaviors of the Crystalline Rock under Dynamic Loads.
Compression-Induced Tensile Mechanical Behaviors of the Crystalline Rock under Dynamic Loads.
复制标题
动态载荷下结晶岩石的压缩诱导拉伸力学行为
DOI：
10.3390/ma13225107
复制
发表时间：
2020-11-12
期刊：
影响因子：
--
通讯作者：
Guo S
中科院分区：
文献类型：
--
作者：
Zheng B;Qi S;Huang X;Liang N;Guo S
岩石在动荷载作用下的拉伸力学行为的表征对实际工程具有重要意义。然而，到目前为止，它的微观力学研究很少。本文采用颗粒模型（GBM），利用通用离散元程序（UDEC）对结晶岩石的压缩诱导拉伸力学行为进行了细观力学研究。结果表明，结晶岩石的拉伸行为具有速率和非均匀性依赖性。基本上，动态巴西拉伸强度以线性的方式增加的加载速率增加。随着颗粒尺寸分布和形貌的不均匀性减弱，颗粒尺度的不均匀性增强，且这种趋势随着加载速率的增加而明显增强。此外，随着颗粒异质性的减弱，速率依赖性变强。颗粒的非均匀性显著影响了人造结晶岩内部的应力分布，特别是在压张混合带。由于材料的非均匀性，在试样中会产生拉应力集中（TSC），这会导致试样的微裂纹和强度弱化。随着晶粒非均匀性的减弱或加载速率的增加，TSC的大小有减小的趋势，并有一个从尖锐的TSC向平滑的拉应力分布区过渡的过程。加载速率对结晶岩的渐进破坏有显著影响，主要表现为两个加载点附近破碎带的形成。研究结果对实际工程如地下工程的应力波防护具有一定的指导意义。
Characterization of the tensile mechanical behaviors of rocks under dynamic loads is of great significance for the practical engineering. However, thus far, its micromechanics have rarely been studied. This paper micromechanically investigated the compression-induced tensile mechanical behaviors of the crystalline rock using the grain-based model (GBM) by universal distinct element code (UDEC). Results showed that the crystalline rock has the rate- and heterogeneity-dependency of tensile behaviors. Essentially, dynamic Brazilian tensile strength increased in a linear manner as the loading rate increased. With the size distribution and morphology of grain-scale heterogeneity weakened, it increased, and this trend was obviously enhanced as the loading rate increased. Additionally, the rate-dependent characteristic became strong with the grain heterogeneity weakened. The grain heterogeneity prominently affected the stress distribution inside the synthetic crystalline rock, especially in the mixed compression and tension zone. Due to heterogeneity, there were tensile stress concentrations (TSCs) in the sample which could favor microcracking and strength weakening of the sample. As the grain heterogeneity weakened or the loading rate increased, the magnitude of the TSC had a decreasing trend and there was a transition from the sharp TSC to the smooth tensile stress distribution zone. The progressive failure of the crystalline rock was notably influenced by the loading rate, which mainly represented the formation of the crushing zone adjacent to two loading points. Our results are meaningful for the practical engineering such as underground protection works from stress waves.
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DOI：
10.1016/0148-9062(94)90005-1
发表时间：
1994-12-01
期刊：
INTERNATIONAL JOURNAL OF ROCK MECHANICS AND MINING SCIENCES & GEOMECHANICS ABSTRACTS
影响因子：
--
作者：
MARTIN, CD;CHANDLER, NA
通讯作者：
CHANDLER, NA
DOI：
10.1016/0148-9062(73)90015-6
发表时间：
1973-01-01
影响因子：
7.2
作者：
HALLBAUER, DK;WAGNER, H;COOK, NGW
通讯作者：
COOK, NGW
影响因子：
5.4
作者：
Hofmann, Hannes;Babadagli, Tayfun;Zimmermann, Guenter
通讯作者：
Zimmermann, Guenter
影响因子：
2.4
作者：
Nguyen, Duc-Hanh;Azema, Emilien;Sornay, Philippe
通讯作者：
Sornay, Philippe
影响因子：
3.9
作者：
Lan, Hengxing;Martin, C. Derek;Hu, Bo
通讯作者：
Hu, Bo