水胶比和纤维掺量对水工ECC干缩特性的影响Effect of water binder ratio and fiber content on the drying shrinkage characteristics of hydraulic ECC
李盼盼,蒋文广,李明霞,孙杨兴
摘要(Abstract):
水工ECC是基于水工建筑物的抗裂需求与技术特点,将ECC应用于水工工程的重大尝试。配制了水工ECC材料,并保持拌合物扩散度相当,测试分析了水胶比和纤维掺量对水工ECC干缩特性的影响。研究表明,水工ECC的干缩变形主要发生在7 d龄期内,28 d龄期时干缩率趋于稳定;增大水胶比时,用水量略有增加,胶凝材料用量随之减小,此外,砂子用量增加,水工ECC的干缩率减小;PVA纤维有利于阻碍水分散失,抵消毛细孔负压,增加PVA纤维掺量,水工ECC的干缩率有所减小;砂子最大粒径越小,水工ECC的干缩率越大。
关键词(KeyWords): 水工ECC;干缩特性;水胶比;PVA纤维;砂子粒径
基金项目(Foundation): 安徽省引江济淮集团有限公司科技资助项目(YJJH-ZT-ZX-20210408381)
作者(Author): 李盼盼,蒋文广,李明霞,孙杨兴
DOI: 10.13928/j.cnki.wrahe.2025.S1.125
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