Effect of Curing Condition and Solvent Content on Mechanical Properties of Zein-Biopolymer-Treated Soil

The curing condition and solvent composition of biopolymer binders may impact their efficacy for soil stabilization. This study introduces a novel hydrophobic biopolymer, zein, and investigates the effects of solvent and curing conditions on the mechanical properties of zein-treated soils. The zein biopolymer is used to prepare cohesionless soil with various ethanol contents. Unconfined compressive strength and microscopic tests are used to investigate the treated specimens under two different curing conditions. The mechanical properties of the treated specimens are evaluated in terms of compressive strength and the secant elastic modulus. The experimental results show that the compressive strength and elastic modulus increase with the curing period under both curing conditions. Higher curing temperature improves the compressive strength of biopolymer-treated specimens. The linear relationship between compressive strength and the elastic modulus of zein-treated soils shows higher strength and a lower elastic modulus compared to rock. Furthermore, the zein biopolymer shows significant strength improvement compared to the existing biopolymers, including casein and lignin. Thus, the effects of solvent and curing conditions on the mechanical properties of zein-treated soil should be considered for its application to soil stabilization.