水胶比对自密实混凝土内部相对湿度分布特征和收缩应变的影响规律研究  

The research on the Influence of the Law of Relative Humidity Distribution Characteristics and Shrinkage Strain Inside Self-compacting Concrete by Water-binder Ratio

作　　者：马良 MA Liang(Guangdong Provincial Quality Test Center of Transportation Construction Project)

机构地区：[1]广东省交通运输建设工程质量事务中心

出　　处：《广东建材》2024年第9期30-34,共5页Guangdong Building Materials

摘　　要：采用温湿度传感器和振弦式应变计,在单面干燥条件下,研究了不同水胶比对自密实混凝土不同深度(距离混凝土试件干燥表面25mm、75mm、125mm处)内部相对湿度分布、收缩应变及其之间相关性的影响。结果表明,水胶比分别为0.35、0.38、0.40、0.43时,相对湿度饱和阶段结束时间(相对湿度发展阶段初始时间)随深度越大,时间越长,同时水胶比越大混凝土内部相对湿度越大;混凝土水胶比在0.35~0.43范围内,水胶比越大,混凝土内部收缩应变绝对值逐渐增大且不同深度层之间收缩应变差别明显;实测相对湿度较混凝土内部相对湿度较晚,相对湿度饱和阶段,收缩应变已变化,相对湿度发展阶段,收缩混凝土的收缩变形与ln(RH)存在线性关系。Using temperature and humidity sensors and vibrating wire strain gauges,the effects of dif‐ferent water-binder ratios on the internal relative humidity distribution,shrinkage strain and their correlation at different depths of self-compacting concrete(25mm,75mm,and 125mm from the dry surface of the concrete specimen)were studied under dry conditions on one side.The results show that when the water-binder ratio is 0.35,0.38,0.40,and 0.43,the end time of the relative humidity saturation stage(the initial time of the relative humidity development stage)increases with the depth,and the time is longer,the relative humidity is higher inside the concrete;The concrete water-binder ratio is in the range of 0.35-0.43,the larger the water-binder ratio is,the greater the absolute value of the internal shrinkage strain of the concrete and the obvious difference between the different depth lay‐ers;The measured relative humidity is later than the relative humidity inside the concrete.In the relative humidity saturation stage,the shrinkage strain has changed.In the relative humidity develop‐ment stage,the shrinkage deformation of the shrinking concrete has a linear relationship with ln(RH).

关 键 词：机制砂 自密实混凝土 相对湿度 收缩应变 

分 类 号：TU528[建筑科学—建筑技术科学]