Failure Patterns and Morphological Soil-Rock Interface Characteristics of Frozen Soil-Rock Mixtures under Compression and Tension
Failure Patterns and Morphological Soil-Rock Interface Characteristics of Frozen Soil-Rock Mixtures under Compression and Tension
复制标题
DOI：
10.3390/app11010461
复制
发表时间：
2021-01-01
影响因子：
2.7
通讯作者：
Hu, Ruilin
中科院分区：
文献类型：
--
作者：
Hu, Feng;Li, Zhiqing;Hu, Ruilin
寒冷地区的施工作业可能会遇到冻结的地质材料。在施工中，重要的是要了解的过程中，地质材料在常见的负载条件下，以避免事故和工作效率。采用人工冻结土石混合体进行单轴压缩和间接拉伸加载试验，研究其宏观破坏模式和土-岩界面裂纹演化机理。为了进一步了解和比较土-岩界面的细观力学破坏机制，我们使用了两种类型的岩石块体颗粒具有不同的表面粗糙度制备冻结人造土石混合物。利用声发射（AE）、超声波加速度（UPV）和数字显微镜技术，获得了土-岩界面的变形响应，并分析了土-岩界面的形态。结果如下。从宏观上看，鼓包变形和短裂纹是压缩破坏的主要形式，而盘中心的曲折裂纹是间接拉伸破坏的主要形式。从微观观察的角度来看，对于含有粗糙岩块的试样，土-岩界面将演化为土-岩接触带。土-岩接触带的强度明显大于土-岩界面的强度。土-岩界面的三种主要破坏模式被观察到：通过精确的土-岩界面的裂纹路径，通过粗糙的岩石块的包络线的裂纹路径，和通过粗糙的岩石块的裂纹路径。试验结果可为基础工程特别是寒区桩基工程提供参考。
Construction operations in cold regions may encounter frozen geomaterials. In construction, it is important to understand the processes by which geomaterials fail under common loading conditions to avoid accidents and work efficiently. In this work, an artificial frozen soil-rock mixture was used for uniaxial compression and indirect tension loading analysis to investigate macroscopic failure patterns and soil-rock interface crack evolution mechanisms. To further understand and compare the meso-mechanical failure mechanisms of the soil-rock interface, we used two types of rock block particles with different surface roughness for fabricating frozen artificial soil-rock mixtures. Acoustic emission (AE), ultrasonic plus velocity (UPV), and digital microscopy were utilized here to obtain the sample deformation response and analyze the morphology of the soil-rock interface. The results were as follows. From the perspective of macroscopic observation, bulging deformations and short tension cracks represent the main failure pattern under compression, and a tortuous tension crack in the center of the disk is the main failure pattern under indirect tension. From the perspective of microscopic observation, the soil-rock interface will evolve into a soil-rock contact band for the sample containing a rough rock block. The strength of the soil-rock contact band is obviously larger than that of the soil-rock interface. Three main failure patterns of the soil-rock interface were observed: a crack path through the accurate soil-rock interface, a crack path through the envelope of the rough rock block, and a crack path passing through the rough rock block. The experimental results could provide a reference for foundation engineering, especially in pile foundation engineering in cold regions.