基于固废源高活性粉体材料的3D打印混凝土

3D printed concrete based on high active powder material of solid waste source

选用固废源高活性粉体材料和P·O 42.5级水泥,辅助石英砂骨料和缓凝型聚羧酸系减水剂、纤维素醚、可分散乳胶粉等辅料制备混凝土3D打印材料并进行性能研究。以3D打印材料凝结时间、胶砂流动度和抗压强度作为评价依据,分析各组分对材料性能的影响,结合极差分析确定最优配合比,采用SEM对3D打印材料1 d水化产物进行表征。优化后制备的3D打印材料凝结时间85 min,初始胶砂流动度190 mm,30 min胶砂流动度180 mm,材料1 d抗压强度28.8 MPa,3 d抗压强度49.6 MPa,28 d抗压强度70.2 MPa。所制备的材料其性能满足混凝土3D打印系统施工需求并能保证打印材料30 min左右仍具有较好的可打印性,该3D打印材料成本约为363.6~437元/t。

The 3D printing material of concrete was prepared by using high activity powder of solid waste source,P.O 42.5 cement as-sisted quartz sand aggregate,slow setting polycarboxylic acid water-reducing agent,cellulose ether,dispersible latex powder and other auxiliary materials.Setting time,fluidity and compressive strength of 3D printed materials were used as evaluation basis to analyze the in-fluence of each component on material properties,and the optimal ratio was determined by range analysis.The 1 d hydration products of 3D printed materials were characterized by SEM.The optimized 3D printing material was prepared with setting time of 85 min,initial mortar flu-idity of 190 mm,30 min mortar fluidity of 180 mm,1 d compressive strength of 28.8 MPa,3 d compressive strength of 49.6 MPa,28 d compressive strength of 70.2 MPa.The material properties of the prepared material meet the construction requirements of concrete 3D printing system and can ensure that the printing material still has good printability for about 30 min.The cost of the 3D printing material is about from 363.6 yuan/t to 437 yuan/t.