预湿陶砂对混凝土板早期湿度分布及发展的影响  

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

作　　者：韩宇栋[1,2] 张君[2] 紫民[3] 

机构地区：[1]中冶建筑研究总院有限公司 [2]清华大学土木工程系 [3]中国人民解放军91058部队

出　　处：《建筑材料学报》2017年第3期326-332,共7页Journal of Building Materials

基　　金：国家自然科学基金资助项目(51478018);国家重点研究发展计划(2016YFC0701003);中冶建筑研究总院有限公司青年科技创新人才项目(YBP2014Ky02)

摘　　要：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.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 mit igated, 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 60 kg/ma , the globle IRH of high- and moderate- strength concrete slabs stays above 92 ~ within 28 days. The lower the matrix water-binder ratio, the stron ger the positive internal curing effect of PSLWA, and the thinner the zone affected by surface-drying. Howev er, internal curing by PSLWA could not eliminate the surface-drying effect of high-, moderate- and low strength concrete slabs under indoor dry environment.

关 键 词：预湿陶砂轻骨料 混凝土板 内养护 内部相对湿度 湿度梯度 

分 类 号：TU528.0[建筑科学—建筑技术科学]