Experimental investigation on the axial compressive behavior of 3D-printed cementitious panels with process-induced imperfections

Additive manufacturing with cement-based materials is increasingly being explored for structural applications in the construction sector. While significant advances have been made in materials and process development, the reliable prediction of structural performance - among the others, the compressive strength at the element scale - remains an open research challenge, especially in the absence of dedicated design codes. This study presents an experimental investigation on the axial compressive behavior of 3D-printed hollow wall panels made with cementitious mortar. In particular, a series of monotonic uniaxial tests were carried out to assess the influence of geometric configuration, printing-induced imperfections, and material properties on the uniaxial compressive response. The results revealed a predominantly brittle failure mode in all specimens. Variability in strength and damage patterns was closely linked to cross-sectional irregularities and layer thickness variation, whereas the in-plane aspect ratio of the panels was characterized by a limited influence exhibited only for larger H/L ratios. The findings highlight critical aspects for modelling and design, suggesting the need for refined qualification procedures for 3D-printed structural elements under compressive loads.