摘要
针对西北寒旱区超长池体水泥基材料的干燥收缩开裂问题,系统开展镁质高性能抗裂剂、粉煤灰、矿粉粉体材料单掺、双掺以及不同养护环境(标准养护、自然养护及覆膜养护)对砂浆干燥收缩性能的影响规律研究,并基于CEB 90 Code Model模型建立不同养护条件下砂浆干燥收缩模型,以对其干燥收缩率进行预测。结果表明:随着养护龄期的增长,超长池体砂浆的干缩率逐渐增大;当镁质高性能抗裂剂掺量控制在≤6%时,不同养护条件下砂浆干燥收缩均得到一定程度改善;单掺粉煤灰试件在不同养护条件下干缩率明显较小;基于CEB 90 Code Model修正的砂浆干燥收缩模型对砂浆早期收缩率预测效果良好。研究结果及收缩模型可为进一步研究大体积混凝土干缩变形问题提供理论依据。
To address the problem of dry shrinkage cracking in ultra-long concrete pools in the arid and cold northwest region,a systematic study was conducted on the effects of magnesium-based high-performance anti-cracking agents,fly ash and slag powder on the dry shrinkage performance of concrete specimens,as well as the influence of different curing environments(standard curing,natural curing,and film-covered curing)on the dry shrinkage properties of the specimens.A dry shrinkage model was established for the specimens based on the CEB 90 Code Model to predict the dry shrinkage rate.The results show that as the curing age increases,the dry shrinkage rate of ultra-long concrete pools increases gradually;When the magnesium-based high-performance anti-cracking agent content is controlled at≤6%,the dry shrinkage of concrete specimens is improved to some extent under different curing conditions;The dry shrinkage rate of single-added fly ash specimens is significantly smaller under different curing conditions;The dry shrinkage model established for concrete specimens based on the CEB 90 Code Model can accurately predict the early dry shrinkage rate of the specimens.The research results and the shrinkage model can provide a theoretical basis for further studies on the drying shrinkage deformation of mass concrete.
作者
伍山雄
薛翠真
银克俭
刘玉果
WU Shanxiong;XUE Cuizhen;YIN Kejian;LIU Yuguo(China State Construction Engineering Corporation,Beijing 100020,China;School of Civil Engineering,Lanzhou University of Technology,Lanzhou 730050,China)
出处
《粉煤灰综合利用》
2025年第4期7-12,共6页
Fly Ash Comprehensive Utilization
基金
国家自然科学基金青年科学基金项目(52108219)
甘肃省青年科技基金项目(20JR5RA440)
中国建筑第四工程局有限公司科技项目(1602202000219004)。
关键词
超长池体
干燥收缩
镁质高性能抗裂剂
养护方式
收缩模型
super long pool body
drying shrinkage
magnesium high performance anti-cracking agent
maintenance mode
shrinkage model
作者简介
伍山雄(1975-),男,本科,高级工程师,研究方向:施工技术、建筑材料;通信作者:薛翠真(1990-),女,博士,副教授,研究方向:建筑垃圾再生利用及混凝土耐久性。
