混凝土抗离析剂的制备及性能研究

Study on the preparation and performance of anti-segregation agent for concrete

通过混凝土试验对不同抗离析原材料进行了筛选,然后将聚乙烯醇与元明粉、麦芽糊精、固体消泡剂按质量比3∶3∶3∶1复配,混合均匀制备成一种混凝土抗离析剂K1,研究了该混凝土抗离析剂对混凝土和易性、坍落度损失、凝结时间及抗压强度的影响。结果表明,离析混凝土中掺入抗离析剂K1后,与基准混凝土相比,扩展度减小≥50 mm,满足施工要求;K1的掺入对聚羧酸减水剂的保坍性能无不利影响,2 h混凝土坍落度损失为10 mm;对凝结时间无明显影响,并且可明显提高混凝土的抗压强度。

Different anti-segregation agents were selected through concrete tests.Polyvinyl alcohol is compounded with sodium sulfate,maltodextrin,and solid defoamer in a ratio of 3∶3∶3∶1,and mixed uniformly to prepare a concrete anti-segregation agent K1.The paper studies the influence of concrete anti-segregation agent on concrete workability,slump loss,setting time and compressive strength in detail.The test results show that the concrete extensibility decreases≥50 mm compared with the benchmark,after adding the newly developed anti-segregation agent K1,which meets the construction requirements.Compared with the benchmark,the incorporation of K1 has no adverse effect on the slump retention performance of the polycarboxylate superplasticizer,the slump loss of 2 h concrete is 10 mm,the setting time of concrete is not affected obviously and the compressive strength of concrete is improved.