坍落度与减水剂对混凝土早期开裂性能的影响  

Effect of the Workability and Superplasticizers on the Early-age Cracking Behaviors of Concrete

作　　者：王雪芳[1] 郑建岚[1] 

机构地区：[1]福州大学土木工程学院,福建福州350108

出　　处：《厦门大学学报（自然科学版）》2008年第5期681-685,共5页Journal of Xiamen University：Natural Science

基　　金：国家自然科学基金(50478003);福建省自然科学基金重大项目(2002F007)资助

摘　　要：混凝土的早期收缩开裂问题已成为国内外专家的研究热点，为了研究混凝土必不可少的组成之一的减水剂对混凝土开裂性能的影响。采用福州大学的发明专利“水泥基材料抗裂性能测试诱导开裂法及其装置”进行减水剂品种和由减水剂掺量改变而导致混凝土坍落度变化对混凝土早期开裂性能的影响试验研究．试验研究结果表明：外加剂品种对混凝土的开裂性能有一定的影响．掺三聚氰胺系减水剂混凝土的抗裂性能优于掺萘系和聚羧酸系减水剂混凝土，掺萘系减水剂混凝土的抗裂性能最差．而且，即使同属萘系减水剂，不同的厂家、不同品牌的减水剂对混凝土开裂性能的影响也不尽相同．混凝土的坍落度对混凝土的开裂性能有一定的影响，坍落度在11～18cm之间的混凝土抗裂性能相对较好．The early-age cracking behaviors of concrete is one of the heat points regarding the concrete research. The superplasticizers are the necessary components of concrete. The effect factors of the variety of superplasticizers and the slump of fresh concrete with various superplasticizers content on the early-age cracking behaviors of concrete were studied. And,the inducing crack method developed by Fuzhou University was adopted to test the early-age cracking behaviors of concrete. The results indicated that the variety of superplasicizers showed some influence on the early-age cracking behaviors of concrete. The early-age cracking behaviors of concrete with melamine-based superplasticizer prevailed over polycarboxylate-based superplasticizer and naphthalene-based superplasticizers. And the early-age cracking behaviors of concrete with naphthalene-based superplasticizer were inferior to others. Additionally, the early-age behaviors of concrete varied with different brand naphthalene-based superplasticizers. And,the slump of fresh concrete also affected the early-age cracking behaviors of concrete. The early-age cracking behaviors of concrete with slump between 11 cm to 18 cm were better than among other slump ranges.

关 键 词：混凝土 早期开裂性能 减水剂 坍落度 

分 类 号：TU528.53[建筑科学—建筑技术科学]