岩土力学2025，Vol.46Issue(6)：1678-1686,9.DOI:10.16285/j.rsm.2024.1286
点载作用下页岩岩屑史氏硬度尺度效应研究
Scale effect on Schmidt hardness of shale cuttings under point load
摘要
Abstract
The high cost of shale coring limits the application of the Schmidt hardness method based on core samples.This study employs cuttings sieving,sample preparation,and point load testing to reveal variation patterns in the ultimate compressive strength of cuttings with different fragment shapes and sizes,establishing a conversion model between cuttings and core Schmidt hardness.Experimental results show that:(1)Shale cuttings are categorized into four shapes:blocky,wide flaky,elongated,and narrow flaky.(2)The ultimate compressive strength of blocky and wide flaky cuttings decreases with increasing dimensions of the long,intermediate,and short axes,and then stabilizes.No significant pattern is observed for narrow flaky and elongated cuttings.(3)The initial dimensions of the stable stage of ultimate compressive strength are 8.2 mm for the long axis,5.9 mm for the intermediate axis,and 3.2 mm for the short axis,and results beyond these dimensions exhibit strong stability.(4)The Schmidt hardness of cuttings is lower than that of the core test results.However,a strong correlation exists between the two,with a correlation coefficient exceeding 0.9.The findings provide a low-cost,real-time evaluation method and standard for shale Schmidt hardness,offering a basis for drilling optimization.关键词
史氏硬度/页岩岩屑/岩屑形状/极限压强Key words
Schmidt hardness/shale cuttings/cuttings fragment shape/ultimate compressive分类
建筑与水利引用本文复制引用
张立刚,李浩,李庆龙,袁胜斌,刘照义,姬建飞,马媛媛,李钧儒,宋永扬..点载作用下页岩岩屑史氏硬度尺度效应研究[J].岩土力学,2025,46(6):1678-1686,9.基金项目
国家自然科学基金(No.51904075,No.52374034) （No.51904075,No.52374034）
黑龙江省自然科学基金(No.LH2022E018).This work was supported by the National Natural Science Foundation of China(51904075,52374034)and the Natural Science Foundation of Heilongjiang Province(LH2022E018). （No.LH2022E018）
