高吸水性树脂颗粒对混凝土自收缩与强度的影响  

Effect of Super Absorbent Polymer Particles on Autogenous Shrinkage and Compressive Strength of Concrete

作　　者：胡曙光[1] 周宇飞[1] 王发洲[1] 彭波 

机构地区：[1]武汉理工大学材料科学与工程学院,湖北武汉430070 [2]武汉市商品混凝土管理站,湖北武汉430015

出　　处：《华中科技大学学报（城市科学版）》2008年第1期1-4,16,共5页Journal of Huazhong University of Science and Technology

基　　金：国家自然科学基金(50572077);武汉市青年科技晨光计划基金(20055003059-8)

摘　　要：自收缩是导致高强混凝土早期开裂的重要因素。研究了高吸水性树脂(SAP)的掺量、引入水量对不同水胶比混凝土的自收缩与强度的影响规律。结果表明,将不超过胶凝材料总重量0.5%的SAP预吸水后掺入混凝土中,可显著减小混凝土的自收缩,且抗压强度损失较小。通过研究SAP对混凝土内部相对湿度变化的影响规律,分析了其对混凝土自收缩与强度的作用机理,认为引入预吸水SAP可明显延缓混凝土早期内部相对湿度的下降速度,对混凝土起到良好的内养护作用,减小自收缩。但当SAP掺量大于胶凝材料总重量的0.5%时,作用效果随SAP掺量的增大而不明显,混凝土抗压强度也有明显下降。Autogenous shrinkage （AS） is an important factor that results in early age crack of high strength concrete. Effects of super absorbent polymer （SAP） dosage and its entrained water on AS and compressive strength of concrete were studied. Results indicate that if dry SAP dosage is within 0.5% of cementitious materials by weight, pre-saturated SAP particles could effectively mitigate AS with little strength loss. Mechanism of SAP on AS and compressive strength were analyzed by investigating internal relative humidity （IRH） change of concrete incorporated with pre-saturated SAP. SAP could delay IRH decline and have an effective internal curing to reduce AS. But when SAP dosage exceeds 0.5 %, internal curing effect improves slightly and compressive strength loss becomes serious.

关 键 词：混凝土 高吸水性树脂 自收缩 内部相对湿度 

分 类 号：TU528.0[建筑科学—建筑技术科学]