预湿陶砂对混凝土板早期湿度分布及发展的影响

研究了室内单面干燥条件下预湿陶砂轻骨料(PSLWA)掺量(体积分数)及水胶比(质量比)对高、中、低强混凝土板28d内部相对湿度(IRH)分布及发展的影响.结果表明:随PSLWA掺量增大,高、中、低强混凝土板湿度饱和期延长,板湿度水平整体提高,湿度下降延缓,板厚方向上湿度梯度减小,湿度饱和区面积比例增大;引入内养护水约60kg/m~3,高、中强混凝土板28d内部相对湿度可维持在92%以上;随基体水胶比降低,PSLWA内养护作用增强,表面干燥影响深度减小;PSLWA不能彻底消除室内单面干燥条件下高、中、低强混凝土板中的表面干燥效应.

Influence of Pre soaked Light Weight Aggregate on Early Age Interior Humidity Distribution and Development in Concrete Slab

Influences of pre soaked light weight aggregate(PSLWA) volume fraction and water binder ratio on early age interior relative humidity(IRH) distribution and development of high , moderate and low strength concrete slabs with casting surface exposed to indoor environment were investigated. Results show that with the increase volume fraction of PSLWA, the early age globle IRH of concrete slabs are gradually increased, the duration of humidity saturated stage is noticeably prolonged, the IRH reduction process is delayed and mitigated, the IRH non linear gradients along the slab thickness are reduced, and the ratio of IRH saturated zone is increased. As the internal curing water reaches about 60kg/m3, the globle IRH of high and moderate strength concrete slabs stays above 92% within 28 days. The lower the matrix water binder ratio, the stronger the positive internal curing effect of PSLWA, and the thinner the zone affected by surface drying. However, internal curing by PSLWA could not eliminate the surface drying effect of high , moderate and low strength concrete slabs under indoor dry environment.