Numerical simulation of elastic buckling in 3D concrete printing using the lattice model with geometric nonlinearity

Abstract

This paper explores buildability quantification of randomly meshed 3D printed concrete objects by considering structural failure by elastic buckling. The newly proposed model considers the most relevant printing parameters, including time-dependent material behaviors, printing velocity, localized damage and influence of sequential printing process. The computational uniaxial compression tests were first conducted to calibrate age-dependent elastic modulus and yield stress. Subsequently, analyses of the 3D printing process of a free wall structure and a square layout were performed. The model can reproduce the asymmetry of buckling failure accurately and the predicted critical printing height is in excellent agreement with experimental data from the literature. It can be concluded the combined effect of material variability and non-uniform gravitational loading due to sequential printing process resulted in structural failure during 3D concrete printing. Using this model, printing parameters can be optimized and a suitable printing scheme can be devised to improve structure buildability.