矿物掺合料对高强混凝土塑性开裂影响的研究.pdfVIP

学兔兔 2010年第5期 混凝土与水泥制品 2010 No5 10月 CHINA CONCRETE AND CEMENT PR0DUCTS 0ctober 矿物掺合料对高强混凝土塑性开裂影响的研究 张守治 ，汪守淳 ，乔艳静 ，陆海梅 (1．江苏博特新材料有限公司，南京210008；2．厦门市建筑工程检测中心有限公司，361000) 摘 要：采用自行改进的集中约束平板法测试系统，研究了粉煤灰、矿渣微粉及硅灰等矿物掺合料对低水胶比高强混凝土出现 塑性裂缝的初始开裂时间、24h内最大裂缝宽度和裂缝总面积的影响。结果表明：粉煤灰的掺入能有效抑制低水胶比高强混凝土的 塑性开裂，推迟裂缝出现的初始开裂时问，减小最大裂缝宽度和裂缝总面积；矿渣微粉的掺人在低掺量下对低水胶比高强混凝土 的塑性开裂有一定的抑制作用，但在高掺量下有增大低水胶比高强混凝土塑性开裂的趋势；硅灰的掺入加剧了低水胶比高强混凝 土的塑性开裂，表现为出现塑性裂缝的初始开裂时间提前和裂缝总面积的增大。 关键词：粉煤灰；矿渣微粉；硅灰；高强混凝土；塑性开裂 Abstract：In order to evalu~e the effects of the mineral admixtures on the plastic cracking properties of high strength concrete，such as initial cracking time，m~imum crack width and total area of cracks，a lot of tests are carried out by the centralized constrained plate method．The experimental results show that，the incorporation of fly ash could effectively inhibit the plastic cracking of high strength con— crete，delay the initial cracking time and reduce the maximum crack width and total cracking area of concrete．Slag could inhibit the plas— tic cracking of high strength concrete with the range of low dosage，but with the increasing dosage of slag，the trend of plastic cracking of high strength concrete increased．Silica fume could increase the plastic cracking of high strength concrete，with the increasing dosage of silica fume，the initial cracking time is ahead and total cracking area of concrete increased． Key words：Fly aM；Slag powder；Silica fume；High strength concrete；Plastic cracking 中图分类号：TU528 文献标识码：A 文章编号：1000-4637{2010)05—24-04 O 前言