New Technologies for Earth Construction (2025-11)¶

The construction industry is on the brink of a revolutionary transformation with the advent of new technologies designed to address the pressing demands of sustainability, efficiency, and affordability. Among these innovations, 3D printing using earth materials stands out as a particularly intriguing development. This technique, which leverages locally sourced soil, proposes a paradigm shift from traditional construction methods. However, as with any emerging technology, it prompts a critical question: is 3D printing for earth construction a tangible solution to be adopted, or is it merely a futuristic vision that remains out of reach? This discussion explores the current state of 3D printing with earth materials, examining its practical applications, technological advancements, and the challenges that must be overcome to determine whether it is a present-day reality or an elusive mirage. This study specifically sought to identify the key mixture variables that impact the properties of a local and Portuguese stabilised earth, potentially suitable for 3D printing, and to determine the appropriate ranges for further investigation. To achieve this, a 23 central composite design (CCD) approach was employed to develop statistical models capable of describing fresh properties such as slump and other engineering characteristics like mechanical performance, resistivity, and mass loss. As such, a central composite design (CCD) was followed to find statistical models capable of describing those key stabilised earth mixtures properties in function of mixture input parameters: water to solids volume ratio (Vw/Vp); superplasticiser to cement weight ratio (Sp/p); cement to soil weight ratio (c/s).