冲击荷载作用下EPS混凝土动态性能研究

配置聚苯乙烯(Expanded Polystyrene,EPS)颗粒体积掺量分别为10%,20%,30%,40%,50%的EPS混凝土,采用Φ100 mm分离式霍普金森压杆(SHPB)试验装置,以动态抗压强度和临界应变为指标,研究EPS混凝土在冲击荷载作用下的动态性能,探索EPS颗粒对混凝土动态性能的改善机理。结果表明:由于应变率效应,相同体积掺量的EPS混凝土动态抗压强度与临界应变随应变率的增加而提高,具有显著的应变率相关性;以临界应变为变形性能指标,由于EPS颗粒的微结构效应,在EPS颗粒体积掺量0～40%范围内,其变形性能随EPS体积掺量的增加而提高,当EPS颗粒体积掺量达到50%时,其变形能力有所降低。EPS颗粒体积掺量为40%时对混凝土变形性能的改善效果最佳。

Dynamic mechanical property of expanded polystyrene concrete under impact loading

The(expanded polystyrene,EPS) concrete with 10%,20%,30%,40%,50% EPS volume fraction were prepared.Taking critical strain and dynamical compressive strength as indexes,the dynamic properties of EPS concrete with different EPS volume fraction under impact loading were studied using a 100-mm-diameter split Hopkinson pressure bar(SHPB) apparatus.The dynamical mechanism of the concrete was discussed.The results demonstrate that the critical strain and dynamical compressive strength of EPS concrete increase with the increase of average strain rate,showing an obvious correlation between the strain rate and the dynamic property.Due to the EPS microscopic structure effect,the deformation property of EPS concrete increases with the increase of EPS volume fraction within the range of 0 ~ 40%.Its deformation property reduces somewhat when the EPS volume fraction reaches 50%.The optimum volume fraction of EPS is 40%.