Bai Er-Lei, Xu Jin-Yu, Lu Song, Lin Ke-Xin, Zhang Yi-Ming
Department of Airfield and Building Engineering, Air Force Engineering University Xi'an 710038 China
College of Mechanics and Civil Architecture, Northwest Polytechnic University Xi'an 710072 China.
RSC Adv. 2018 Apr 18;8(26):14454-14461. doi: 10.1039/c8ra00082d. eCollection 2018 Apr 17.
In this paper, two types of lightweight porous concrete material, expanded polystyrene concrete (EPSC) and ceramics-cement based porous material (CCPM) have been prepared on the base of C60 concrete. The dynamic mechanical experiments of lightweight porous concretes have been carried out by 100 mm split Hopkinson pressure bar (SHPB) improved by wave shaping technology. The dynamic properties, including strength properties, deformation properties, impact toughness and energy absorption properties, of lightweight porous concretes have been analyzed comparatively, and its application prospects have been discussed. The results show that the two types of lightweight porous concretes are strain rate sensitive. Dynamic compression strength increases with strain rate; the correlation between the peak strain, ultimate strain of lightweight porous concrete and strain rate can be expressed by quadratic polynomial; under the impact loading, the impact toughness of lightweight porous concretes increases with strain rate, the amount of absorbed energy increases with the average incident energy change rate, moreover, the relation between the impact toughness and strain rate, and that between the amount of absorbed energy and the average incident energy change rate can both be expressed by exponential functions; compared with EPSC, CCPM has better properties in terms of strength, deformation, impact toughness and energy absorption. Those advantages are more obvious with high strain rate. Therefore, CCPM has more vast application prospects in civil defense projects than EPSC.
本文以C60混凝土为基础,制备了两种轻质多孔混凝土材料,即聚苯乙烯泡沫混凝土(EPSC)和陶瓷 - 水泥基多孔材料(CCPM)。采用波形整形技术改进的100mm分离式霍普金森压杆(SHPB)对轻质多孔混凝土进行了动态力学试验。对轻质多孔混凝土的动态性能,包括强度性能、变形性能、冲击韧性和能量吸收性能进行了对比分析,并探讨了其应用前景。结果表明,两种轻质多孔混凝土均具有应变率敏感性。动态抗压强度随应变率的增加而增大;轻质多孔混凝土的峰值应变、极限应变与应变率之间的关系可用二次多项式表示;在冲击荷载作用下,轻质多孔混凝土的冲击韧性随应变率的增加而增大,吸收能量的量随平均入射能量变化率的增加而增大,且冲击韧性与应变率之间的关系以及吸收能量的量与平均入射能量变化率之间的关系均可用指数函数表示;与EPSC相比,CCPM在强度、变形、冲击韧性和能量吸收方面具有更好的性能。在高应变率下,这些优势更为明显。因此,CCPM在人防工程中的应用前景比EPSC更为广阔。