Inferring the Early-Age Young’s Modulus of 3D-Printed Mortar Through Inverse Analysis Using Actual Print Data (2026-03)¶

Three-dimensional concrete printing has advanced rapidly in recent decades, yet standardized methods for characterizing early-age mechanical properties, essential for stable print design, remain lacking. This study presents an improved non-destructive inverse analysis method to estimate the early-age, time-dependent tangent Young’s modulus of 3D-printed mortar from actual print data. The hypothesis is that layer deformations can be represented through a lumped Young’s modulus that captures all effects governing the measured layer deformations and serves as the key parameter to predict buckling instability during printing. The work includes: (i) 3D printing of test structures, (ii) 3D laser scanning of printed geometry, (iii) numerical modeling of print heights and buckling instability, and (iv) an optimization strategy that minimizes differences between scanned and simulated layer heights to identify the evolution of Young’s modulus. Using the identified time-dependent Young’s modulus, the onset of buckling instability is predicted within 0.4 to 2.1 layers of the observed collapse at 10 layers, corresponding to a relative deviation in the range 4%-21%. While still under development, results indicate the method captures key early-age material mechanics, as indicated by strong agreement between simulations and experimental collapse observations.