内养护预拌混凝土性能与应用研究

Study on properties and application of internal curing commercial concrete

研究了高吸水树脂（SAP）对高水胶比普通预拌混凝土工作性能、力学性能、收缩性能的影响,结果表明SAP的引入会在一定程度上增加外加剂的掺量,比普通预拌混凝土约提高0.1%~0.2%。SAP对混凝土的早期强度有一定的负面影响,后期强度比普通混凝土略高。SAP对预拌混凝土的干燥收缩有较好的补偿作用,有助于降低开裂风险。对比了内养护预拌混凝土,膨胀剂混凝土及普通混凝土在高温炎热环境条件下的道面应用效果,结果表明内养护混凝土应用效果良好,而膨胀剂混凝土及普通混凝土地坪均有不同程度的开裂,显示出内养护技术对于解决混凝土的干燥收缩开裂问题具有较好的效果。

The effect of super absorbent polymers（ SAP）on the workability,mechanical and shrinkage properties of high water-binder ratio ready-mix concrete was studied. Results indicate that the dosage of admixture increase by 0.1%~0.2%with the introduction of SAPs and the SAPs had a negative effect on the early-age strength of ready-mix concrete,however a positive effect on the later strength. The SAPs compensated the dry shrinkage of ready-mix concrete well which was beneficial to reduce the dry cracks. Moreover,the pavement application effects of internal curing ready-mix concrete,expansive concrete and ordinary concrete were compared under high tempera-ture environment. It turned out that the internal curing ready-mix concrete performed well,however the expansive concrete and the ordi-nary concrete both had different degrees of cracking,which proved that the internal curing technique was efficient to reduce the dry shrinkage and cracks of commercial concrete.