Experimental study on crack evolution characteristics of rock-like materials under different strain rates. (19th June 2018)

• Record Type: Journal Article
• Authors: Shugang, Li; Xuanhong, Du; Pengxiang, Zhao; Peng, Xiao; Haifei, Lin; Haiqing, Shuang
• Is Part Of: Journal of geophysics and engineering. Volume 15:Number 5(2018:Oct.)
• Page Start: 2071
• Page End: 2078
• Publication Date: 2018-06-19
• Subjects: crack evolution -- uniaxial compression -- strain rate -- peak intensity; Geophysics -- Periodicals; Prospecting -- Geophysical methods -- Periodicals; Engineering -- Periodicals; 622.1505
• DOI: 10.1088/1742-2140/aabb66
• Languages: English
• ISSNs: 1742-2132

Abstract

Abstract: In order to study the influence of fracture evolution characteristics of rock-like materials under different strain rates, we use river sand as aggregate and cement, and gypsum and starch as binder to make a rock-like specimen, and uniaxial compression experiments are carried out with different loading rates by a DYD-10 electronic universal testing machine. The average strain rate of rock samples under different loading rates was obtained, and the characteristics of crack evolution of rock samples under different strain rates were studied. The results show that with the increasing strain rate, the peak strength of rock-like specimen increases; the main fracture gradually develops to the direction paralleled to the maximum principal stress, which leads the failure form of the specimen evolving from shear failure to tensile failure. During the loading process, the specimen will enter the plastic stage from the elastic stage, and a certain 'reaction time' which increases with the increase of strain rate is needed. The energy rate which is released inside the specimen increases with the strain rate from slow to fast, then from fast to slow, allowing the surface crack to extend in the same trend; that is with the increase of strain rate, the specimens exhibit obvious brittle failure, and the average evolutionary rate of specimen surface increases logarithmically following the strain rate. Therefore, the study on the crack evolution characteristics of rock-like materials under different strain rates can provide some theoretical bases for similar physical simulation experiments.