As opposed to massive concrete structures, 3D-printed concrete structures have a high surface-to volume ratio, leading to high water loss after printing. This evaporation is known to cause significant plastic shrinkage shortly after printing, which often leads to cracks. We demonstrate experimentally that effects of evaporation are also visible at the hardened state, with a significant impact on the compressive strength of printed parts, evaporation being detrimental to the compressive strength. Based on experimental observations indicating a positive correlation between printed wall thickness and compressive strength at the hardened state, and an increase in the compressive strength when preventing evaporation after printing, we propose a fully coupled thermo-poro-mechanical model to describe the evolution of the printed material, from fresh to hardened state. Cement hydration and associated stiffness and strength build-up, as well as water evaporation at the boundaries, water transport within the printed structure and water consumption due to cement hydration are accounted for. Their effects on temperature, strain, stiffness and compressive strength evolution are studied, and compared with experimental data. Comparisons between model predictions and experimental results demonstrate the model’s validity, enabling estimations of both shrinkage and strength development in 3D-printed cementitious structures in given environmental conditions. Indeed, the findings confirm that, in the absence of protective measures to limit water evaporation, thinner walls suffer from greater plastic shrinkage and lower cement hydration, stiffness and compressive strength than thicker walls. Additionally, experimental and numerical investigations confirm that preventing evaporation enhances compressive strength, reaching that of traditionally cast samples. These results highlight the importance of curing strategies in concrete 3D-printing. The model offers a predictive framework to estimate the efficiency of various curing strategies on several parameters, from short- to long-term after printing, and allows to estimate the hardened properties of printed part given the actual environmental conditions.