纤维高强混凝土的动态力学性能试验研究  

EXEPERIMENTAL STUDY ON DYNAMIC MECHANICAL PROPERTIES OF FIBER REINFORCED HIGH STRENGTH CONCRETE

作　　者：杜修力[1] 窦国钦[1] 李亮[1] 田予东[1] 

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124

出　　处：《工程力学》2011年第4期138-144,150,共8页Engineering Mechanics

基　　金：国家自然科学基金重点项目(50638030);国家"十一.五"科技支撑项目(2006BAJ13B02)

摘　　要：为研究纤维高强混凝土材料在冲击荷载下的动态压缩性能,采用大尺寸φ75mm Hopkinson压杆,对三种纤维含量的钢纤维高强混凝土、PVA纤维高强混凝土试件进行了三种应变率范围的冲击压缩试验,得到了它们在较高应变率范围内的动态应力-应变关系。试验表明纤维高强混凝土材料为应变率敏感性材料,在较高应变率范围内纤维高强混凝土材料的动态应力-应变关系是与应变率相关的。纤维高强混凝土材料的破坏应力和破坏应变随应变率的增大而增大。钢纤维和PVA纤维对混凝土耗能能力的改善和提高表现在材料达到峰值应力后开始破坏的过程中。同时也对两种纤维高强混凝土材料的纤维增韧特性及耗能机理也进行了分析和探讨。A large size Split Hopkinson Pressure Bar（SHPB） of 75mm was used to study the dynamic mechanical behavior of fiber reinforced high strength concrete under an impact loading.The impact compression experiments with three different strain rate ranges were conducted for steel fiber reinforced high strength concrete specimens and polyvinyl alcohol fiber（PVA） reinforced high strength concrete specimens with three fiber contents.The results show that at high strain rate,the dynamic stress-strain relationships are strain rate dependent.It means that the fiber reinforced high strength concrete is sensitive to the strain rate.The failure stress and failure strain increase with increasing the strain rate.The energy absorbing capability of the steel fiber and PVA fiber in concrete is exhibited in the process of the material failure only after the peak stress is reached.The mechanism of the toughness increasing effect and energy absorbing of fiber reinforced high strength concrete is also analyzed and discussed.

关 键 词：分离式霍普金森压杆 钢纤维高强混凝土 PVA纤维高强混凝土 动态力学特性 冲击压缩试验 

分 类 号：TU377[建筑科学—结构工程] TU502