粉煤灰、矿粉对水工混凝土体积稳定性的影响

采用对比的方法,实验研究了粉煤灰、矿粉对水工混凝土的工作性、抗压强度、弹性模量、干缩和受压徐变的影响。结果表明,在粉煤灰、矿粉等量取代部分水泥后,混凝土的工作性改善,抗压强度和抗压弹模与基准样相近,而28d以后的干缩明显减小;掺有粉煤灰、矿粉的混凝土随养护龄期的延长、强度的增加,其受压徐变逐渐减小;当粉煤灰掺量(质量分数)从15%增加到25%时,混凝土的徐变增大;对于相同掺量(15%)的粉煤灰、矿粉混凝土,经60d养护后加荷其徐变基本相同。

Influence of Fly Ash and Slag on Volume Stability of Hydraulic Engineering Concrete

In this paper,some performances that included workability,compressive strength,elastic module,drying shrinkage and creep,were tested for hydraulic engineering concrete with and without fly ash or slag.The results showed that for concrete with fly ash or slag,the workability of the fresh concrete was improved;the compressive strength and the elastic module were similar to the control sample,but the drying shrinkage rate decreased after 28 d;the creep decreased with the increasing of the curing time and the strength,and increased with the content of fly ash from 15% to 25%.The creep for concrete with 15% fly ash was similar with that for one with 15% slag when the load was applied after 60 d curing.