Haidong Zhuang ^a , Zhenbang Guo ^a , Yuanwang Lan ^a , Cristina Ruiz-Agudo ^b , Fazhou Wang ^a , Helmut Colfen ¨ ^b , Zhengyao Qu ^a,b,*

Thermal-responsive soil-hydrogel composite for additive construction

Journal of Building Engineering 98 (2024) 111118

To improve the formability and bonding strength of 3D printing soil, a temperature-stimulating responsive intelligent soil-hydrogel 3D printing formula was innovatively developed by combining soil and gelatin. Varied soil-gelatin composites, featuring different gelatin content by weight of soil (0%, 0.5%, 1%, and 1.5%), were prepared and cured at 5 ℃ to facilitate the crosslinking of gelatin. An array of tests, including rheological assessments, compressive tests, and scanning electron microscopy analysis. were conducted to thoroughly characterize the performance of gelatin-soil composites for 3D printing. Our findings unveiled that, following the cross-linking of gelatin at 5 ℃, the gelatin-soil composites exhibited superior formability and bond strength compared to the reference. Furthermore, the soil-gelatin composites demonstrated not only comparable compressive strength to the reference but also enhanced interlayer bond strength. This innovative soil-hydrogel 3D printing formula, combining the versatility of soil and the responsive characteristics of gelatin, presents a promising avenue for advancing the capabilities of 3D printed soil.