水利学报2025，Vol.56Issue(3)：287-296,10.DOI:10.13243/j.cnki.slxb.20240477
层理砂岩的双K断裂参数与尺寸效应试验研究
Experimental study on the size effect of double K fracture parameters in stratified sandstone
摘要
Abstract
Sandstone,as a representative sedimentary rock,is commonly encountered in engineering problems such as tunnel excavation and slope stability.As a typical quasi-brittle material,the fracture properties of sand-stone are crucial mechanical characteristics in engineering applications.To investigate the influence of bedding plane orientation and specimen size on the double K fracture parameters of sandstone,this study conducted system-atic three-point bending fracture tests using beam specimens with heights of 10,20 and 40 mm,and bedding an-gles of 0°,30°,60° and 90°,respectively.Complete macroscopic response curves,fracture parameters,and failure modes were obtained through the experiments,confirming that the fracture process of sandstone can be fully described using the double K fracture model.Both the dip angle of bedding and the specimen height significantly af-fect the double K fracture parameters:with a constant specimen height,the peak load,unstable fracture tough-ness,and initiation fracture toughness decrease as the bedding dip angle increases,while with constant bedding plane orientation,the peak load and unstable fracture toughness increase with specimen height,but the initiation toughness remains relatively unchanged,further verifying it as an inherent material property.Additionally,the failure modes of the specimens exhibit clear anisotropic characteristics based on bedding plane orientation,showing a mixed failure mode of tension and shear as the bedding dip angle increases.关键词
砂岩/双K断裂模型/层理倾角/试样高度/破坏模式Key words
sandstone/double K fracture model/bedding inclination angle/sample height/failure mode分类
建筑与水利引用本文复制引用
徐世烺,韩明捷,王庆敏,刘福深..层理砂岩的双K断裂参数与尺寸效应试验研究[J].水利学报,2025,56(3):287-296,10.基金项目
国家自然科学基金重点项目(5238003) （5238003）
