高吸水树脂应用于混凝土内养护领域的研究进展

Research Progress of Superabsorbent Polymer Applied in the Field of Concrete Curing

低水灰比混凝土在具备高性能的同时,往往因为结构致密、渗透性差,外部养护的水分难以进入,其内部相对湿度低,进而引起混凝土的自收缩和开裂现象。在低水灰比混凝土难以与外部实现水分交换的情况下,高吸水树脂(super absorbent polymer, SAP)由于具有出色的吸水和保水性能,可作为内养护剂,用以减少混凝土早期自干燥和自收缩,抑制裂纹的产生。通过综述SAP的分类、合成与制备及其吸水机理,概括了SAP在混凝土内养护领域的研究现状。重点总结了SAP对混凝土力学性能、耐久性能以及收缩性的影响;并展望了SAP在混凝土内养护领域的研究方向。

Low water-cement ratio concrete,while possessing high performance,often has a dense structure and poor permeability,making it difficult for external curing water to penetrate.As a result,the internal relative humidity is low,leading to self-shrinkage and cracking of the concrete.In the case of concrete with a low water-cement ratio,where water exchange with the outside is difficult,super absorbent polymer(SAP)can be used as an internal curing agent to reduce early-stage self-drying and self-shrinkage of concrete and to inhibit cracking due to its excellent water absorption and retention properties.By reviewing the classification,synthesis,preparation,and water absorption mechanism of SAP,this article summarizes the current research status of SAP in the field of concrete internal curing.It focuses on the effects of SAP on the mechanical properties,durability,and shrinkage of concrete,and looks ahead to the research directions of SAP in the field of concrete internal curing.