镁渣混凝土的早期抗裂.pdfVIP

学兔兔 2015年 第 10期(总 第312期 ) 混 凝 土 原材料及辅助物料 Number 10 in 2015(Total No．312) Concrete MATERIAL AND ADMINICLE doi：10．3969~．issn．1002—3550．2015．10．018 镁渣混凝土的早期抗裂 崔自治，王建峰。陈东东，万清琦 (宁夏大学土木与水利工程学院，宁夏银川750021) 摘 要：针对镁渣利用率低，以及对现代混凝土尺寸稳定性要求高的问题，以镁渣掺量、粉煤灰取代率为因素，设计单因素及正 交试验方案，试验研究镁渣混凝土的早期抗裂性。结果表明：混凝土单位面积的总开裂面积与镁渣掺量呈下凹的二次曲线关系， 与水分蒸发率有显著的线性相关性。在镁渣掺量不大于30％时，混凝土的早期抗裂性随镁渣掺量的增加而增大，镁渣掺量大于 30％后，随镁渣掺量的增加转而趋于恶化，镁渣的最优掺量约为30％。镁渣和粉煤灰对混凝土的早期开裂均有抑制效应，镁渣的 作用效应明显的强于粉煤灰的作用效应，掺入适量的镁渣可以提高混凝土的早期抗裂性。 关键词：混凝土；镁渣；收缩补偿；早期抗裂 中图分类号：TU528．04 文献标志码：A 文章编号：1002—3550(2015)10—0071—04 Early cracking of magnesium slag concrete CU／Zizhi，WANG Jianfeng，CHENDongdong，WAN Qingqi (College of Civil and Hydraulic Engineenng，Ningxia University，Yinchuan 750021，China) Abstract：In view of the low utilization rate of magnesium slag，high size stability requirement of modem concrem problem，taking magnesium slag content and fly ash replacement rate as main factors，orthogonal test scheme was designed to study the early crack re— sistance of magnesium slag concrete by experiment．Results showed that：total crack area per unit area of concrete and magnesium slag content is concave quadratic relationship，significant linear correlation with water evaporation rate；The early crack resistance of concrete increases with increasing magnesium slag content when magnesium slag content is not more than 30％，worsening when more than 30％， the optimum magnesium slag content is about 30％．Magnesium slag and fly ash have inhibitory effect on early cracking of concrete，the effect of magnesium slag is obviously stronger than fly ash ．appropriate amo