Dynamic characteristics and crack evolution laws of coal and rock under split Hopkinson pressure bar impact loading
نویسندگان
چکیده
Abstract The aims of this paper are to comprehensively explore both the dynamic mechanical properties and crack evolution characteristics coal rock during impact failure. First, experimental specimens prepared from seam, direct roof strata floor in same area highlight correlations between test pieces. Second, a strain gauge high-speed (HS) camera adopted reflect stress wave signal evolution. Then, based on digital image correlation (DIC) technology mass screening method, laws surface cracks crushing distribution sample fragments after studied perspective fractal, finally compared with those simulation analysis. results as follows. (1) samples have consistency differences. affected by velocity physical specimen. Higher speeds densities lead more obvious brittleness specimen when destroyed. Conversely, shows plasticity ductile yield. (2) self-similarity is significantly manifested impact. box dimension quality applicable quantitatively characterize process fractures. (3) Holmquist–Johnson–Cook (HJC) Riedel–Hiermaier–Thoma (RHT) constitutive models agree well results, RHT model consistent. This study may contribute comprehensive understanding under loading provide references for further research discussion.
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ژورنال
عنوان ژورنال: Measurement Science and Technology
سال: 2023
ISSN: ['0957-0233', '1361-6501']
DOI: https://doi.org/10.1088/1361-6501/acca3b