混杂纤维高韧性水泥基复合材料抗压性能研究

Compression Performance of Hybrid Fiber High Toughness Cementitious Composites

为改善传统单掺有机纤维水泥基材料的抗压性能,采用钢纤维+聚乙烯纤维混杂方式制备了一种高韧性水泥基复合材料,在聚乙烯(PE)纤维体积掺量固定为1%的情况下,考虑钢纤维体积掺量分别为0、0.3%、0.6%、0.9%4种工况下该水泥基复合材料的抗压试验,分析了钢纤维掺量、长度、直径对其抗压性能的影响。结果表明,采用钢纤维与PE纤维混杂方式可显著提高水泥基复合材料的抗压性能,在采用较长钢纤维的情况下,较低的体积掺量可以有效提升试件的抗压强度,直径越小的钢纤维试件抗压性能越好。对比发现,钢纤维直径0.12mm、长度13mm、体积掺量为0.6%时混杂效应较好,其峰值压应力较未掺钢纤维的试件提升33.8%,极限压缩应变提升24.3%。

In order to enhance the compressive behavior of common engineered cementitious composites with inorganic fiber,a novel high toughness cementitious composites by means of fiber-hybrid mode was produced.The volume percentage of polyethylene(PE)fiber was designed as a constant 1%and four kinds of volume percentage of steel fiber(0,0.3%,0.6%,and 0.9%)were adopted in this hybrid-fiber mode.Compression test is conducted with the variable analysis including fiber length,fiber diameter as well as fiber percentage.The experimental results show that the hybrid manner of steel fiber plus PE fiber could effectively improve the compressive strength of high toughness cementitious composites.The compression performance of the hybrid steel-PE fiber is improved obviously.The specimens with lower volume content of PE fiber will perform higher compressive strength in which steel fiber with longer length is used,and furthermore,the specimens using steel fiber with smaller diameter present better strength.Based on the comparison of different hybrid modes,the specimens show comparative hybrid effect when the steel fiber with diameter of 0.12 mm,length 13 mm and volume percentage 0.6%isadopted.Compared with the specimens without steel fiber,the peak compression strength of specimens with optimum hybrid fiber mode has an increase of 33.8%,and the maximum compression strain increases by 24.3%.