Yue Jianwei, Li Peng, Zhao Limin, Huang Xuanjia, Xu Xiangchun, Wang Zifa
School of Civil Architecture, Henan University, Kaifeng 475004, China.
Kaifeng Key Laboratory of Restoration and Safety Evaluation of Immovable Cultural Relics, Kaifeng 475004, China.
Materials (Basel). 2022 Jun 1;15(11):3941. doi: 10.3390/ma15113941.
Fracture characteristics are the basis of silty clay fracture research, and its quantitative description is helpful to explore the engineering properties of silty clay. The silty clay samples with different moisture contents and different aspect ratios were prepared by the controlled variable method for the drying shrinkage test. The crack image processing and crack feature extraction were performed by PS and IPP software, and the relationship between the crack propagation characteristic parameters and the change in humidity and sample moisture content during drying shrinkage were analyzed to explore the crack development law. The results show that under the continuous action of the environment, cracks were generated at the initial high temperature (46 °C). When the temperature changed from a high temperature (46 °C) to a low temperature (27 °C), the moisture content decreased faster, and the crack developed rapidly. Later, from low temperature (12 °C) to high temperature (46 °C), the water content and crack parameters remained basically unchanged; the cracks of the samples with a high moisture content appeared early, developed rapidly, and damaged seriously. When the aspect ratio was 6:1, the crack developed vertically, and when the aspect ratio was less than 6:1, the secondary crack was about 90° from the upper crack.
裂隙特性是粉质黏土裂隙研究的基础，对其进行定量描述有助于探究粉质黏土的工程性质。采用控制变量法制备不同含水率、不同高宽比的粉质黏土试样进行干燥收缩试验。利用PS和IPP软件进行裂纹图像处理及裂纹特征提取，分析干燥收缩过程中裂纹扩展特征参数与湿度、试样含水率变化之间的关系，以探究裂纹发育规律。结果表明：在环境持续作用下，初始高温（46℃）时产生裂纹；当温度由高温（46℃）变为低温（27℃）时，含水率下降较快，裂纹迅速发育；之后，由低温（12℃）到高温（46℃），含水率及裂纹参数基本保持不变；高含水率试样裂纹出现早、发育快、破坏严重。当高宽比为6∶1时，裂纹垂直发育，当高宽比小于6∶1时，次生裂纹与上部裂纹夹角约为90°。
