采用直锥变截面式Φ74mm分离式霍普金森压杆,对不同替代率沙漠砂混凝土进行冲击压缩实验,得到了不同替代率沙漠砂混凝土在不同应变率下的应力应变曲线。分析应变率对沙漠砂混凝土峰值应力、峰值应变和比能量影响,揭示了沙漠砂替代率对沙漠砂混凝土峰值应力影响规律,并对沙漠砂混凝土动态破坏模式进行研究。研究表明:随着应变率增加,沙漠砂混凝土峰值应力、强度增强因子、比能量和峰值应变逐渐增大;在同一应变率下,随着替代率增加,沙漠砂混凝土峰值应力逐渐减小。本文研究结果可为沙漠砂在工程中的应用提供指导和借鉴。
Straight cone variable cross section split Hopkinson pressure bar (SHPB) with 74mm diameter was adopted to study the dynamic mechanical properties of desert sand concrete with different desert sand substitution ratios. Stress-strain curves of desert sand concrete with different desert sand substitution ratios and under various strain rates were obtained. The influence of strain rate on the peak stress, peak strain and specific energy of desert sand concrete was analyzed. The effect of desert sand substitution ratio on the peak stress of desert sand concrete was revealed. At the same time, the dynamic failure mode of desert sand concrete was studied. Experimental results show that with the increase of strain rate, the peak stress, stress intensity factor, peak strain and specific energy of desert sand concrete increase. At the same strain rate, the peak stress of desert sand concrete decreases with the enhancement of desert sand substitution ratio. Above results may provide guidance and reference in engineering application of desert sand.