Nanomaterial And Cellulosic Rheology Modifiers For 3D Concrete Printing

摘要

Viscosity and static yield stress are significant rheological properties for 3D concrete printing (3DCP), in which process high static yield stress is associated with high buildability and shape stability and low viscosity is associated with extrudability and pumping. The challenge in concrete rheology lies in decoupling the effect of admixtures on these two properties, i.e., achieving high static yield stresses while still maintaining moderately low viscosities. In meeting this challenge, provided here is an additive system of nanoclays and viscosity modifying admixtures that can tailor the rheological properties of cement composites to meet 3DCP performance requirements. Further, because 3DCP is a technology of scales, any additive must meet scalability and stability requirements for construction, i.e., ease of processing in abundance and relatively low cost, and exhibit an extended shelf life.