自密实混凝土的制备及其在钢管混凝土中的应用

Design Method of Self-compacting Expansive Concrete and Application in Concrete Filled Steel Tube

制备出了具有较高强度、较优工作度和膨胀性能的自密实混凝土,采用目前通用的收缩率计算公式和膨胀率计算公式对普通混凝土和膨胀混凝土进行了计算,并与实际测量结果进行了比较,发现普通自密实混凝土的早期收缩率发展很快,即使在密封的条件下也会产生较大的收缩,目前常用的收缩率计算公式不适用于普通自密实混凝土。膨胀率计算公式适用于本实验条件下膨胀自密实混凝土的膨胀率估算,但是公式中各参数需要根据实际情况进行调整。掺适量延迟膨胀剂能够显著提高钢管膨胀混凝土的极限抗压强度。

Self-compacting expansive concrete that possesses good workability,high strength and expansive properties, is produced.Employing two popular calculation equations,shrinkage rate calculation equation and expansive rate calculation equation,we get the calculated values of ordinary and expansive self-compacting concrete.By comparing those values with testing results,we find the popular shrinkage rate calculation equation of ordinary concrete is not suitable for ordinary self-compacting concrete,but expansive rate calculation equation is good although the factors in the equation should be adjusted depending on the actual situation.The early shrinkage rate of ordinary self-compacting concrete developed very fast although the samples are sealed.The strength of concrete filled steel tube can be improved by proper addition of expansive agent EA.