超高性能水泥基复合材料早期自收缩特性研究

发布时间：2018-06-15 02:34

  本文选题：超高性能水泥基复合材料 + 早期自收缩　； 参考：《建筑材料学报》2014年01期

【摘要】：采用新型高精度全自动自收缩测量仪,研究了加入粗集料、不同水胶比(m_W/m_B=0.16,0.20,0.24)和不同钢纤维体积分数((?)_i=0%,1%,2%,3%)对超高性能水泥基复合材料(ultrahigh performance cementitous composite,UHPCC)自加水起33 h内自收缩特性的影响.结果表明:UHPCC早期自收缩随龄期的发展具有明显的双阶段特征,即初始快速发展阶段和后期缓慢发展阶段;UHPCC早期自收缩随着水胶比的降低而增加,当水胶比从0.24分别减小到0.20,0.16时,0~20 h内其自收缩值分别增加了34.0%和63.8%;粗集料和钢纤维对UHPCC早期自收缩有明显的抑制作用,钢纤维体积分数从0%分别增至1%,2%和3%时,0~33 h内其自收缩值分别降低了23.9%,60.5%,86.5%;UHPCC在33 h时的自收缩值与水胶比(≤0.24)、钢纤维体积分数(0%~3%)这两者的关系均近似呈线性相关.
[Abstract]:In this paper, the effect of adding coarse aggregate, different water / binder ratio and different volume fraction of steel fiber on the autogenous shrinkage of ultrahigh performance cementitous composite material UHPCC within 33 hours was studied by using a new type of automatic autoshrinkage measuring instrument with high precision and different water / binder ratios of 0.16 / 0.20 / 0.24) and different volume fraction of steel fiber. The results showed that the early autoroconstriction of the first stage and the late stage of UHPCC had the characteristics of two stages, I. e., the initial rapid development stage and the late stage of slow development stage, which increased with the decrease of the water-binder ratio, and the ratio of water to binder increased with the decrease of water / binder ratio. When the water-binder ratio decreased from 0.24 to 0.20 ~ 0.16, the autogenous shrinkage increased by 34.0% and 63.8% in 20 h, respectively, and the coarse aggregate and steel fiber had obvious inhibitory effect on the early autogenous shrinkage of UHPCC. The volume fraction of steel fiber increased from 0% to 1%, and the autogenous contraction value of UHPCC decreased 23. 9% 60.5% and 86. 5% in 33 h, respectively, and the relationship between the autogenous shrinkage of UHPCC at 33 h and the ratio of water to binder (鈮，

本文编号：2020186