高吸水树脂吸液特性对混凝土性能的影响

Effect of Super-absorbent Polymer Water Absorption Characteristics on Performance of Concrete

提出了高吸水树脂(SAP)吸水率比指标,研究了吸水率比对SAP在水泥浆体离心液中的吸水动力学及内养护混凝土流变性能、抗压强度、收缩性能的影响。结果表明:SAP在水泥离心液中吸水率呈迅速增加、逐渐降低和最后稳定的规律;当SAP吸水率比增大时,吸水率峰值增大、释水时间延长。伴随SAP吸水率比逐渐增大,内养护混凝土拌合物屈服应力逐渐增大、塑性黏度逐渐降低。SAP可降低混凝土早期强度,对后期强度影响较小,且可明显降低混凝土收缩。在吸水率比为1.94~6.16范围内,SAP对混凝土抗压强度和收缩性能的作用规律一致。

An indicator named as water absorption ratio of super-absorbent polymer(SAP) was proposed. The effect of SAP water absorption ratio on the absorption kinetics of SAP in centrifugal liquid from cement slurry(CLCS), rheological property of fresh concrete with internal curing, compressive strength and shrinkage of hardened concrete with internal curing was investigated. The results indicate that the absorption of SAP in CLCS exhibits a law of rapid increase, gradual decrease and final stability. The peak value of absorption and the release time increase, the yield stress of fresh concrete gradually increases and the plastic viscosity gradually decreases as the SAP water absorption ratio increases. SAP reduces the early strength and shrinkage of concrete significantly, and has little impact on the long-term strength. SAP also has no impact on the compressive strength and shrinkage of hardened concrete evolved with curing time when the water absorption ratio is 1.94-6.16.