当前位置: X-MOL 学术Bull. Eng. Geol. Environ. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Numerical study on strength and failure characteristics of rock samples with different hole defects
Bulletin of Engineering Geology and the Environment ( IF 3.7 ) Pub Date : 2020-09-06 , DOI: 10.1007/s10064-020-01964-y
Shaojie Chen , Zhiguo Xia , Fan Feng , Dawei Yin

In a rock mass, holes of various sizes and geometries naturally occur, which in turn can affect the mechanical properties of the rock mass. These defects often cause engineering problems in subsurface construction. In this study, PFC2D was used to perform uniaxial compression tests on a rock mass containing ten different types of hole defects to analyze their failure behavior and mechanical properties. Four failure modes were determined, and crack propagation and stress field evolution were studied. The results show that the hole defect reduces the uniaxial compressive strength, peak strain, and elastic modulus of a rock mass. Also, these defects accelerate the generation of cracks and promote the destruction of the rock. The failure modes can be classified as Y-type, inverted Y-type, upper left to lower right type, and upper right to lower left type. Before cracks are generated, the compressive stress concentration area is located on the left and right sides of the hole and distributed as a butterfly shape, and the tensile stress concentration area is located in the upper and lower parts of the hole. A zone where stress is decreasing is located near the tip of the tensile stress triangular area. The magnitude and concentration area of compressive and tensile stresses are greatly affected by various hole geometries. Finally, the maximum principal compressive stress decreases instantly after a crack coalesces. Overall, the hole shape has a noticeable influence on the stress distribution surrounding the hole, and a hole defect reduces the degree of failure of a rock mass.



中文翻译:

不同孔缺陷岩石样品强度和破坏特性的数值研究

在岩体中,自然会出现各种尺寸和几何形状的孔,这又会影响岩体的机械性能。这些缺陷通常在地下施工中引起工程问题。在这项研究中,PFC2D用于对包含十种不同类型的孔缺陷的岩体进行单轴压缩测试,以分析其破坏行为和力学性能。确定了四种失效模式,并研究了裂纹扩展和应力场演化。结果表明,孔缺陷降低了岩体的单轴抗压强度,峰值应变和弹性模量。而且,这些缺陷会加速裂纹的产生并促进岩石的破坏。失效模式可以分为Y型,倒Y型,左上至右下,以及从右上方到左下方的类型。在产生裂纹之前,压应力集中区域位于孔的左侧和右侧,并呈蝶形分布,而拉应力集中区域位于孔的上部和下部。应力减小的区域位于拉伸应力三角形区域的尖端附近。压应力和拉应力的大小和集中区域受各种孔几何形状的影响很大。最后,最大主压应力在裂纹合并后立即降低。总体而言,孔的形状对孔周围的应力分布有显着影响,孔缺陷降低了岩体的破坏程度。压缩应力集中区位于孔的左侧和右侧,呈蝶形分布,拉伸应力集中区位于孔的上部和下部。应力减小的区域位于拉伸应力三角形区域的尖端附近。压应力和拉应力的大小和集中区域受各种孔几何形状的影响很大。最后,最大主压应力在裂纹合并后立即降低。总的来说,孔的形状对孔周围的应力分布有明显的影响,孔的缺陷降低了岩体的破坏程度。压缩应力集中区位于孔的左侧和右侧,呈蝶形分布,拉伸应力集中区位于孔的上部和下部。应力减小的区域位于拉伸应力三角形区域的尖端附近。压应力和拉应力的大小和集中区域受各种孔几何形状的影响很大。最终,最大主压应力在裂纹合并后立即降低。总体而言,孔的形状对孔周围的应力分布有显着影响,孔缺陷降低了岩体的破坏程度。拉应力集中区域位于孔的上部和下部。应力减小的区域位于拉伸应力三角形区域的尖端附近。压应力和拉应力的大小和集中区域受各种孔几何形状的影响很大。最后,最大主压应力在裂纹合并后立即降低。总体而言,孔的形状对孔周围的应力分布有显着影响,孔缺陷降低了岩体的破坏程度。拉应力集中区域位于孔的上部和下部。应力减小的区域位于拉伸应力三角形区域的尖端附近。压应力和拉应力的大小和集中区域受各种孔几何形状的影响很大。最后,最大主压应力在裂纹合并后立即降低。总体而言,孔的形状对孔周围的应力分布有显着影响,孔缺陷降低了岩体的破坏程度。裂纹合并后,最大主压应力立即减小。总体而言,孔的形状对孔周围的应力分布有显着影响,孔缺陷降低了岩体的破坏程度。裂纹合并后,最大主压应力立即减小。总的来说,孔的形状对孔周围的应力分布有明显的影响,孔的缺陷降低了岩体的破坏程度。

更新日期:2020-09-06
down
wechat
bug