Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** 3D printed concrete (3DPC) is a…

Awards issued prior to january 20, 2025, were funded under previous administrations and may not reflect the priorities and policies of the current administration.** 3D printed concrete (3DPC) is a rapidly expanding construction technology owing to its pace, material savings, and need for less labor. Despite these advantages, 3DPC suffers from volumetric shrinkage, which should be mitigated to avoid cracking. The heat produced during the exothermic hydration of higher cement content and accelerated evaporation due to the lack of formwork in 3DPC structures are the reasons for volume shrinkage. The goal is to synthesize hydrogel crystals from corn and soybeans to mitigate volume shrinkage in 3DPC. When mixed with concrete, we hypothesize that the biobased hydrogel crystals will serve as internal water reservoirs, releasing water into the cementitious matrix to compensate for the water loss due to exothermic cement hydration and evaporation. Corn starch (CS) and SOY protein isolate (SPI) are chosen, considering their hydrophilicity and compatibility with concrete. The research objectives are to 1) synthesize non-toxic biobased hydrogel crystals from agricultural feedstocks, 2) determine their suitability for concrete applications, 3) evaluate the printability of biobased hydrogel infused concrete (BHIC), 4) quantify the strength and improved shrinkage characteristics of BHIC, and 5) assess the financial viability of biobased hydrogel crystals for volume shrinkage mitigation in 3DPC. The primary deliverables will be the synthesis procedures and shrinkage mitigation capacities of five CS and three SPI hydrogel crystals. Commercializing these biobased hydrogel crystals resolves the volume shrinkage issue in 3DPC, fostering a new market for corn and soybeans, which aligns with the program's goals, potentially offering new jobs and a supplementary income source for US farmers.