CA砂浆干燥收缩与自身相对湿度研究  

Drying Shrinkage and Relative Humidity of CA Mortar

作　　者：王涛[1] 魏曌[1] 刘子科[1] 李洪刚[1] 

机构地区：[1]中国铁道科学研究院金属及化学研究所,北京100081

出　　处：《建筑材料学报》2017年第3期431-434,438,共5页Journal of Building Materials

基　　金：国家自然科学基金资助项目(51408610);中国铁路总公司科技研究开发计划项目(2013G008-A-1)

摘　　要：研究了水泥乳化沥青(CA)砂浆内部相对湿度与干燥收缩以及两者之间的相互关系.结果表明:CA砂浆内部相对湿度在早龄期时较高,之后随龄期延长而下降,且降幅在90d后趋缓;CA砂浆先膨胀后收缩,约7d时达到最大膨胀值,120d后收缩趋缓;水灰比(m_W/m_C)、乳化沥青-水泥比(m_A/m_C)等配合比参数对CA砂浆内部相对湿度和干燥收缩的影响均不明显;在密封养护条件下,CA砂浆试件内部的相对湿度较大且降幅较小,而干燥收缩较少且增幅较小,到后期时比脱模时略有膨胀;不密封养护CA砂浆试件在后期时收缩明显,其相对湿度与干燥收缩线性相关性较好.所得结论可为CRTSⅠ型轨道减少板角离缝提供指导.The relative humidity（RH） and drying shrinkage（DS） of CA mortar and the relationship be- tween them were investigated. Results indicate that RH is high in early age, decreasing with increasing in the age, and slowing down after 90 d CA mortar shrinks after an initial expansion, the highest expansion value appear at about 7 d, and shrinkage decreases down after 120 d; the parameters of mix proportion, such as water-cement ratio （mw/mc）, asphalt-cement ratio （mA/mc）, has no significant influence on RH and DS of CA mortar; under sealed curing, RH of CA mortar is higher and slightly reduces in late stage, and DS of CA mortar is lower and slightly increases, even has a slight expansion in long-term. Under open condition, CA mortar undergoes a high shrinkage at late stage,DS and RH show significant linear relation, which can provide guidance for reducing the crack between slab corner and CA mortar layer in CRTS ]~ track.

关 键 词：CA砂浆 相对湿度 收缩 离缝 

分 类 号：TU528.42[建筑科学—建筑技术科学]