CAJ | 학술논문

采用100 mm分离式霍普金森压杆试验系统，对高温后素混凝土（Plain Concrete，PC）及玄武岩纤维混凝土（Basalt Fiber Reinforced Concrete，BFRC）在冲击荷载作用下破碎块度分布、破碎分维及能耗特性进行研究。结果表明，冲击破坏后试件破碎块度分布为统计意义的分形，温度及弹速的升高导致试件破碎程度及分维值总体增大；BFRC分维在常温及600℃～800℃时普遍小于PC，在200℃～400℃时随弹速提高较PC先减小后增大，纤维掺量为0．2％时BFRC分维相对较大；同一温度下试件能耗密度随分维的增大而增大，相同能耗密度下分维随温度的升高而增大；BFRC分维随弹速的变化有两个临界速度特征点：起裂临界及粉碎临界弹速，在此弹速范围内，试件破碎分形演化特征明显，分维随弹速提高显著增大，且临界弹速随温度的升高逐渐下降。
채용100 mm분리식곽보금삼압간시험계통，대고온후소혼응토（Plain Concrete，PC）급현무암섬유혼응토（Basalt Fiber Reinforced Concrete，BFRC）재충격하재작용하파쇄괴도분포、파쇄분유급능모특성진행연구。결과표명，충격파배후시건파쇄괴도분포위통계의의적분형，온도급탄속적승고도치시건파쇄정도급분유치총체증대；BFRC분유재상온급600℃～800℃시보편소우PC，재200℃～400℃시수탄속제고교PC선감소후증대，섬유참량위0．2％시BFRC분유상대교대；동일온도하시건능모밀도수분유적증대이증대，상동능모밀도하분유수온도적승고이증대；BFRC분유수탄속적변화유량개림계속도특정점：기렬림계급분쇄림계탄속，재차탄속범위내，시건파쇄분형연화특정명현，분유수탄속제고현저증대，차림계탄속수온도적승고축점하강。
The dynamic fragmental characteristics of plain concrete (PC)and basalt fiber reinforced concrete (BFRC)after different temperatures including fragments distribution,fractal dimension and energy dissipation capacities under impact loading were investigated by using a 100 mm diameter split Hopkinson pressure bar (SHPB)apparatus.The experimental results revealed that the fragment distribution of specimens statistically has a fractal property under impact loading.The higher the temperature and projectile velocity,the severer the fragmentation and the larger the fractal dimension;the fractal dimension of BFRC is smaller than that of PC at room temperature and the range of 600 ℃to 800℃;compared with the fractal dimension of PC,that of BFRC decreases firstly and then increases with increase in projectile velocity at the range of 200 ℃ to 400 ℃;the volume fraction of 0.2% basalt fiber leads to a relatively higher fractal dimension of BFRC;the energy dissipation density increases with increase in fractal dimension under the same temperature,the fractal dimension under the same energy dissipation density increases with increase in temperature;there are two critical velocity points in the relationship between the fractal dimension of BFRC and projectile velocity,i.e., initial fracture critical projectile velocity and crushing critical projectile velocity;in this velocity range,the fractal evolution characteristics of fragmentation are obvious,the fractal dimension increases with increase in projectile velocity markedly;when the temperature increases,the critical projectile velocity drops gradually.