Valorization of Peapod Waste as a Pulverized Organic Additive for Sustainable Soil Stabilization

This study investigates the potential valorization of peapod waste—an agricultural by-product commonly discarded during food processing—as a pulverized organic additive for sustainable soil stabilization. Approximately 50% of pea mass is typically lost as pod waste, posing environmental and economic disposal challenges. In this research, peapods were first air-dried, then oven-dried at low temperature to prevent changes in their organic structure. The dried pods were pulverized and incorporated into clayey sand (SC) and low-plasticity clay (CL) soils at 5%, 10%, and 15% proportions under standard Proctor compaction. Unconfined compressive strength (UCS) tests were conducted to assess mechanical improvements. The SC soil exhibited UCS increases of approximately 50%, 75%, and 100% for the respective additive ratios. For the CL soil, 5% addition increased UCS by 20%, while 10% addition led to a slight decrease, though still outperforming the natural soil. All treated samples showed increased axial strain, indicating improved deformability. The results highlight the feasibility of using pulverized peapod waste to enhance the strength characteristics of soils, particularly sandy-clayey types, offering an eco-friendly alternative to conventional stabilizers. This approach supports circular economy principles by repurposing organic waste in geotechnical applications.