Damage-rheology model for predicting 3D printed concrete buildability

Insufficient buildability during printing can result in structural instability of three-dimensional (3D) printed concrete. A damage-rheology model was developed to predict such structural failure by simulating the early-age behavior of 3D printed concrete. The model captures essential characteristics of early-age concrete, including structural build-up, softening damage, irreversible deformation, and creep effect. Based on continuum damage mechanics, the model integrates the damage-plasticity theory and the Burgers model. A time-dependent thixotropic model is used to characterize the structural build-up behavior, considering the evolution of material properties as functions of the structural parameter. The model is systematically validated by comparing its predictions with uniaxial creep, straight-wall printing, and hollow-cylinder printing tests. The study investigates the effect of early-age creep on structural responses. Numerical results demonstrate the ability of the model to accurately predict the buildability of early-age 3D printed concrete.

Automated summary

A damage-rheology model is developed to predict the structural instability of 3D printed concrete caused by insufficient buildability during printing. The model accurately captures the early-age behavior of 3D printed concrete, including structural build-up, softening damage, irreversible deformation, and creep effect.