Effects of Penicillium Fungus on Silty Clayey Soil Properties Using Bio-Inspiration Methods

Soil improvement is a crucial aspect of geotechnical engineering, with various techniques developed to enhance soil properties for diverse applications. Recently, there has been a growing focus on sustainable solutions that are both cost-effective and environmentally responsible. Biological soil improvement, particularly through fungi, offers an innovative approach to enhancing soil characteristics.

This study investigates the impact of a Penicillium chrysogenum strain on physical and mechanical properties of silty clay soil under controlled laboratory conditions. The tested soil was collected in a hilly area of the Northern Italian Apennines, strongly affected by shallow landslide and soil erosion. The research focuses on key soil parameters, including Atterberg limits, water retention curves, erodibility, and mechanical properties (shear strength and oedometer features), utilizing equipment such as the Casagrande device, Hyprop, Wet sieve apparatus, WP4C, oedometer, and direct shear test. For the reconstruction of water retention curves, a coupled system with an evaporation technique apparatus and a dew-point technique was adopted. RETC software, employing the Van Genuchten model and Mualem's hydraulic conductivity model, was applied to analyze the soil retention curve and water potential. The methodologies for adding the fungal suspension into the soil are considered as mixing. This study explores the potential of Fungal suspensions to enhance soil structure and stability through the modification of specific soil properties. In this investigation, the treated soil with the fungus will be compared to the non-treated one.

The findings from this study provide valuable insights into the effectiveness of using bio-remediation methods such as fungal treatment, as a nature-based solution with broad applications in Civil Engineering, Environmental Science, and Geotechnics. Ultimately, these results support the development of sustainable soil enhancement practices that meet both ecological and economic objectives.