CAJ | 학술논문

用大直径（?100 mm）分离式霍普金森压杆径向冲击边裂纹平台圆环试样，测试砂岩的Ⅰ型动态断裂韧度。使用裂纹扩展计（crack propagation gauge，CPG）测定试样起裂时刻和裂纹扩展速度，结果表明裂纹扩展计测定比传统电阻应变片更为灵敏，测定结果更接近裂纹破坏真实情况。用实验-数值法确定了试样的动态起裂韧度，采用实验-数值法并结合普适函数进一步求得砂岩的动态扩展韧度。研究发现在一定范围内动态起裂韧度随加载率的增加而增大，而动态扩展韧度随裂纹扩展速度的变大而略微增加。
용대직경（?100 mm）분리식곽보금삼압간경향충격변렬문평태원배시양，측시사암적Ⅰ형동태단렬인도。사용렬문확전계（crack propagation gauge，CPG）측정시양기렬시각화렬문확전속도，결과표명렬문확전계측정비전통전조응변편경위령민，측정결과경접근렬문파배진실정황。용실험-수치법학정료시양적동태기렬인도，채용실험-수치법병결합보괄함수진일보구득사암적동태확전인도。연구발현재일정범위내동태기렬인도수가재솔적증가이증대，이동태확전인도수렬문확전속도적변대이략미증가。
The edge cracked flattened ring (ECFR) specimens of sandstone were diametrically impacted by large-diameter split Hopkinson pressure bar (SHPB) in the model-I rock dynamic fracture test. Crack prop?agation gauge (CPG) is used to measure the crack initiation time and crack propagation velocity, the CPG is more sensitive than traditional strain gauge, and measured results are closer to reality. The experi?ment-numerical method is used to determine the dynamic initiation toughness, while the universal function combined with experiment-numerical method is adopted to determine the dynamic propagation toughness. The rock dynamic fracture test indicates that, in a certain range, the dynamic initiation toughness and dy?namic propagation toughness increase with increasing dynamic loading rate and crack propagation velocity, respectively.