In the field of petroleum engineering,Shi's hardness serves as a pivotal technical parameter for delinea-ting stratum resistance against drilling and for the optimization of drill bits and drilling methodologies.Presently,Shi's hardness testing is hampered by the absence of unified methodologies and standards,with the influence of di-verse testing factors on outcomes remaining ambiguous.This ambiguity culminates in a lack of comparability a-mongst hardness testing results from various laboratories.This investigation utilized polymethyl methacrylate,ce-ment,and outcrop sandstone as exemplars to explore the selection and preparation of standard test samples and the evaluation process of their physical and mechanical properties from multiple angles,including density,wave speed,CT imaging,and Shi's hardness testing.Moreover,a sensitivity analysis of Shi's hardness testing was executed.Findings reveal that lithology type governs the indentation curve morphology,Shi's hardness values,and the charac-teristics of indentation failure.Shi's hardness test results are significantly influenced by sample size,loading rate,indenter diameter,and indentation position.Hardness values correlate positively with sample size and loading rate,yet inversely with indenter diameter.Indentations situated at the center of the sample manifest higher hardness val-ues compared to those at the edges.This study profoundly investigates the essential factors upon which the stability and accuracy of Shi's hardness test results hinge,facilitating the development of rock hardness assessment and clas-sification standards.
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