添加剂对3D打印轻骨料混凝土流变性和可打印性的影响

Effect of Additives on Rheological Properties and Printability of 3D Printing Lightweight Aggregate Concrete

研究了骨料(石英砂、玻化微珠)、保塑剂(HMC)、塑化剂(KHC)、乳胶粉(FX)对3D打印轻骨料混凝土(3DPLAC)的流变性能、挤出性、堆积性能以及容重的影响.结果表明:在相同水胶比下,随着玻化微珠取代量的增加,3D打印轻骨料混凝土的表观黏度、触变性和屈服应力明显下降,挤出性、堆积性能降低,容重显著下降;随着HMC和KHC掺量的增大,3D打印轻骨料混凝土的表观黏度、触变性、屈服应力均明显增大;随着FX掺量的增加,3D打印轻骨料混凝土的表观黏度、触变性以及屈服应力呈先减小后增大的变化趋势.通过优化各组分配比,3D打印轻骨料混凝土可获得适宜的流变性能,可打印性得到显著改善,容重明显降低.

The effects of aggregates(quartz sand,vitrified bead),thickeners(HMC),plasticizers(KHC),and latex powder(FX)on the rheological properties,extrudability,stacking performance and bulk density of 3D printing lightweight aggregate concrete(3DPLAC)were studied.The results show that the apparent viscosity,thixotropy and yield stress of the 3D printing lightweight aggregate concrete decrease significantly,the extrudability and stacking performance decrease,and the bulk density also decreases significantly with the increase of the replacement amount of vitrified beads under the same water-binder ratio.With the increase of HMC and KHC content,the apparent viscosity,thixotropy and yield stress of 3D printing lightweight aggregate concrete increased significantly.With the increase of FX content,the apparent viscosity,thixotropy and yield stress of 3D printing lightweight aggregate concrete decrease first and then increase.By optimizing the distribution ratio,3D printing lightweight aggregate concrete can obtain appropriate rheological properties,its printability is significantly improved,and its bulk density is also significantly reduced.