SAP吸-释水行为及其对混凝土性能的影响机制综述  

Water Absorption-release Behavior of SAP and Influence Mechanism on Concrete Properties:A Review

作　　者：陈华鑫[1,2] 郑睢宁 何锐 郭健[1,2] 王振军 CHEN Hua-xin;ZHENG Sui-ning;HE Rui;GUO Jian;WANG Zhen-jun(School of Materials Science and Engineering,Chang'an University,Xi'an 710061,Shaanxi,China;Shaanxi School-enterprise Joint Research Center for Advanced Transportation Infrastructure Materials,Xi'an 710064,Shaanxi,China)

机构地区：[1]长安大学材料科学与工程学院,陕西西安710061 [2]陕西省"四主体一联合"先进交通基础设施材料校企联合研究中心,陕西西安710064

出　　处：《中国公路学报》2024年第1期1-19,共19页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(52278429);陕西省重点研发计划项目(2022GY-422,2023-ZDLGY-25);陕西省交通科技项目(20-16K,21-50K,22-29K);长安大学博士研究生创新能力培养项目(300203211312)。

摘　　要：高吸水性树脂(Super-absorbent Polymer,SAP)因其优异的吸、储、释水特性已发展成为理想的混凝土内养护材料之一。为了明晰SAP吸-释水行为与混凝土性能之间的联系,提升SAP的养护效率和混凝土性能,总结了SAP吸-释水的3种理论,系统分析了SAP在不同溶液中的吸-释水行为、SAP与水泥浆体间的水分交换机制及SAP与混凝土内部湿度之间的关系;论述了SAP水分运移行为研究方法,分析了各方法的特点及适用性;从水化行为、孔结构和微观形貌的角度探讨了SAP粒径、掺量及额外引水量对混凝土性能的影响。结果表明:离子网络理论、溶液热力学理论和凝胶相转变理论可以很好的阐释SAP在不同溶液中的吸-释水行为,SAP内部吸附水和毛细水的含量是影响SAP释水周期的关键因素,SAP的吸-释水特性决定了混凝土内部水分的分布;SAP内养护混凝土的微观结构和宏观性能受SAP掺量、粒径和额外引水量等参数综合影响,合适的参数可使水化产物填充SAP释水产生的孔洞,细化混凝土孔结构、提高密实度、改善力学性能并提升耐久性。SAP还可提高混凝土的自愈合能力、提升耐火剥落性及实现藻类在混凝土上的定植等。未来应进一步明确SAP在混凝土内部的形态演变及其在混凝土中的吸-释水动力学行为,阐明SAP与混凝土内部水分分布的相互关系,从而实现对SAP内养护混凝土的精细化设计。Superabsorbent polymer(SAP)has been developed as an optimum internal curing material for concrete owing to its superior absorption,storage,and water release behavior.To better understand the relationship between SAP water absorption-release behavior and concrete performance and increase the curing efficiency of SAP,three theories of SAP water absorption-release were summarized.The water absorption-release behavior in different solutions,water exchange mechanism between SAP and cement paste,and relationship between SAP and concrete internal humidity were systematically analyzed.The test methods of SAP water migration behavior were summarized,and the characteristics and applicability of each method were analyzed.The effects of the SAP particle size,dosage,and entrained water amount on concrete properties were discussed from the perspectives of cement hydration,pore structure,and micro-morphology.The results show that the ionic network,solution thermodynamic,and gel phase transition theories can explain the water absorption-release behavior of SAP in different solutions,and the amount of adsorbed and capillary water in SAP affects the water release time of SAP.The water absorption-release properties of the SAP determine the moisture distribution in concrete.The microstructure and macroscopic properties of SAP internal curing concrete are comprehensively influenced by SAP dosage,particle size,and entrained water amount.Appropriate parameters enable hydration products to fill the pores created by SAP,thus refining the concrete pore structure and improving compactness,mechanical properties,and durability.Additionally,the self-healing capacity,resistance to fire spalling,and algae cultivation of concrete are increased by SAP.To improve the design of the internal curing concrete of SAP,the morphological evolution of SAP and its water absorption-release behavior in concrete,as well as the relationship between SAP and water distribution,should be clarified.

关 键 词：路面工程 混凝土 综述 SAP 内养护 水分运移 影响机制 

分 类 号：U414[交通运输工程—道路与铁道工程]