不同养生方法下早龄期混凝土水分迁移规律  

Patterns of Water Movement Inside Early-age Concrete Subjected to Different Curing Methods

作　　者：张翛[1,2] 赵鸿铎[1] 赵队家[2] 

机构地区：[1]同济大学道路与交通工程教育部重点实验室,上海201804 [2]山西省交通科学研究院,山西太原030006

出　　处：《中国公路学报》2015年第3期20-27,共8页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51308329);山西省青年科技研究基金项目(2013021028-2);山西省自然科学基金项目(2013011027-1);山西省交通建设科技项目(2013-1-10;2013-1-11)

摘　　要：为了研究早龄期混凝土在养生条件下的湿度发展规律,采用湿度传感器对早龄期混凝土内部的相对湿度(RH)进行了测试,分析了3个水灰比试件在3种养生方式下的早龄期混凝土水分迁移规律,建立了考虑养生因子的早龄期混凝土在外部干燥条件下的一维水分迁移模型,并以试验数据为基础对模型的有效性进行了验证。研究结果表明:水灰比对混凝土自干燥效应的影响较大,水灰比越小,自干燥程度越大;空气养生下混凝土内部的湿度降低速率大于养护剂和水养生下的降低速率;同时考虑自干燥和外部干燥效应的混凝土的湿度变化对养生方式较为敏感;在水分迁移模型的狄利克雷边界条件中引入养生因子的概念能较好地描述养生条件下早龄期混凝土的水分迁移规律。In order to study the development of moisture inside cured early-age concrete,the relative humidity（RH）inside early-age concrete was measured by humidity sensor.The water movement patterns of early-age concrete under with three water cement ratios subjected to three commonly used curing methods in concrete pavements were analyzed.A one dimensional water movement model for early-age concrete under external drying with curing factor considered was established.The model was validated using tested data in laboratory.The results show that the effect of water cement ratio on self-desiccation considered is significant.Lower water cement ratio tends to result in larger RH reduction.For RH reducing rate inside concrete the air curing is greater than membrane-forming compound curing and water curing.RH reduction with both effects of external drying and self-desiccation considered in early-age concrete is sensitive to curing method.It can be concluded that incorporating the concept of curing factor in the Dirichlet boundary condition is appropriate for modeling of water movement in cured early-age concrete.

关 键 词：道路工程 水泥混凝土路面 试验研究 水分迁移 相对湿度 养生 自干燥 

分 类 号：U418.6[交通运输工程—道路与铁道工程]