Compression behaviors of cementitious cellular composites with negative Poisson's ratio

Traditionally, mechanical properties of cementitious materials are designed “chemically”, namely by configuring their mix proportions. Owning to the development of 3D printing technology, “physical” tailoring the meso-structure of cementitious materials to design their mechanical properties becomes possible. In the present study, cementitious materials were designed both by configuring the meso-structure and the base material mix proportions. Circle and ellipse cellular structure were designed and molds for casting were prepared by 3D printing technique. Plain mortar (REF) and polyvinyl alcohol (PVA) fiber reinforced mortar (FRM) were used as base material. After casting, curing and demolding, uniaxial compression tests were performed on these cementitious cellular composites. The cellular composites exhibit three stages of compressive fracture behavior, including fracture and deformation of the cellular structure, crushing of the base material and compacting of crushed materials. With ellipse cellular design, negative Poisson’s ratio was achieved during the compression and the overall energy absorption efficiency and deformability was higher than circular design cellular which implies that this cementitious cellular material be a promising impact resistant material.