The leeb (Equotip) hardness test for rock materials: An overview, assessments on the factors influencing test results, and prediction models based on a large database
Reşat Ulusay, Hakan Ersoy, Muhammet Oğuz Sünnetci, Murat Karahan
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引用次数: 0
Abstract
This study aims to assess several factors affecting Leeb hardness (LH) test results for rock materials. Regression models for predicting some strength and deformability properties from LD values were proposed and compared based on a larger database from a comprehensive experimental program conducted and those compiled from the literature. The results indicate that Single Impact Method (SIM) is the most suitable method to obtain more reliable LD values when compared to Repeated Impact Method (RIM). In addition, RIM causes the formation of pits and bulges on the sample surface. 15 single impacts are sufficient to determine LD value that statistically represents optimal number of impacts to be applied. The test should be performed on samples with a length of (L) ≥ 50 mm (L/D ≥ 1) and the impacts should be applied by leaving a minimum distance at least equal to the diameter of the tester supporting ring from sample edge.
期刊介绍:
Engineering geology is defined in the statutes of the IAEG as the science devoted to the investigation, study and solution of engineering and environmental problems which may arise as the result of the interaction between geology and the works or activities of man, as well as of the prediction of and development of measures for the prevention or remediation of geological hazards. Engineering geology embraces:
• the applications/implications of the geomorphology, structural geology, and hydrogeological conditions of geological formations;
• the characterisation of the mineralogical, physico-geomechanical, chemical and hydraulic properties of all earth materials involved in construction, resource recovery and environmental change;
• the assessment of the mechanical and hydrological behaviour of soil and rock masses;
• the prediction of changes to the above properties with time;
• the determination of the parameters to be considered in the stability analysis of engineering works and earth masses.