高吸水树脂(SAP)在高性能和超高性能混凝土内养护效果方面的优越性已得到认同。混凝土中掺加SAP对其内部湿度、水化程度、自收缩和耐久性具有积极作用,但对流动性和强度有不利影响。为了更好研究和利用SAP的内养护效果,本文综述了SAP的种类、吸/释水过程对混凝土内部湿度、孔结构和性能影响等方面的研究进展,认为SAP引水量在水泥水化程度、自收缩与强度之间的平衡点和SAP孔与毛细孔的连通性是评价其总体作用效果的关键点,并且SAP分子结构设计、在水泥浆体中吸液动力学、颗粒尺寸与覆盖范围的关系、饱和度和内养护水可利用性的关系需要进一步研究。
The superiority of superabsorbent polymer (SAP) as an internal curing agent of high or ultra-high performance concrete was represented. The SAP has a positive effect on the concrete internal humidity, hydration degree, autogenous shrinkage and durability, but has a negative effect on the fluidity and compressive strength. In this paper, the relevant results on the type and the water absorption/release process of SAP, and the effect of SAP on the internal humidity, pore structure and performance of concrete were summarized. The evaluation on the overall effect of SAP should consider the connectivity of SAP pore and capillary pores, and the amount of SAP entrained water meeting cement hydration degree, autogenous shrinkage and compressive strength. Some aspects on the design of the molecular structure of SAP, dynamically simulation of the water absorption and release process of SAP in cement paste, and the establishment of their relationships need to be further studied.