Experimental Study on the Effect of Water-Binder Ratio on 3D Printing Form of Concrete Mortar (2025-07)¶

Concrete 3D printing, also known as concrete “additive construction”, 3D printing technology for printable cement-based materials put forward the following requirements, that is, the newly mixed slurry must have good pumpable, extrudable performance, that is, the material through the nozzle is not blocked, not segregated; The material in the accumulation process should have good interlayer bonding performance and good long-term shape retention ability, no deformation, no collapse. There are many factors affecting this requirement, among which the water-adhesive ratio has a particularly important effect on the printing effect of mortar. The research team used ordinary Portland cement, silica ash, fly ash, polyethylene fiber PE, quartz sand, water reducing agent, early strength agent and water as raw materials to stir into printing mortar, and set the water-binder ratio of 0.2–0.28 as the interval to conduct mortar molding state experiments. The experiments confirmed that when the water-binder ratio of 0.22–0.24, the formation of printed specimens did not deform or collapse. The extrudability of mortar with a water-binder ratio of 0.24 is better.