Study on criticality of coarse aggregate content on early-age properties of 3D printable concrete

This study deals with the criticality of binder-coarse aggregate interaction in the early age properties of 3D printable concrete (3DPC). The concrete with coarse aggregate (CA) behaves as two-phase material and has different rheological behavior. The transient early age concrete material properties are significant in simulating the plastic material yielding and elastic buckling failure patterns of 3DPC. Triaxial compression test (TCT) was adopted to measure apparent transient properties of 3DPC by Mohr-Coulomb criteria. Though this test methodology was adopted by some researches earlier for 3D printable mortars, a contradictory failure pattern was observed for 3DPC with CA of size 4 mm to 8 mm. The unconfined uniaxial compressive test (UUCT) was also performed to measure the green compressive strength and failure patterns were observed.