Material Properties of Eco-friendly Composite Using Gelatin as an Organic Binder according to the Mix Proposition

Gelatin is a protein-derived material that is a biological medium and a binder that can exhibit mechanical performance. In previous studies, a new concept of Living Building Material (LBM) was suggested using gelatin as a medium for cyanobacteria, but research on the mechanical performance of LBM according to the gelatin mix proposition was insufficient. In this study, the effect of mix proposition on the mechanical performance of a sand-gelatin solution composite was investigated. As a result, the mechanical performance of it was expressed as the gelatin crosslink formed between sand particles. The flexural or compressive strength ratio of the sand-gelatin composite was higher than that of the cement mortar since the bond strength of the gelatin solution to the mineral substrate exceeded that of the cement paste. The concentration of the gelatin solution had a greater effect on the compressive strength than the solution or sand ratio; in the case of a 20% gelatin solution, the average compressive strength at 28 days of curing was expressed to be up to 7.59MPa. On the contrary, the properties of the fresh-state composite were majorly affected by the gelatin or sand ratio while the flow and setting time tended to increase as the ratio increased.