Natural zeolite impacts on liquefaction stabilization of oil-contaminated silica sands – physical and chemical evaluation

• Zeolite is an eco-friendly construction material employed as an oil-polluted silica sand stabilization agent. • Soils in oil-rich nations are jeopardized by oil contamination. • Liquefaction mitigation risk is critical in civil engineering since it could endanger structures and buildings established on the soil. • This paper used a simple shear device, besides FTIR and SEM evaluations, to find the effectiveness of zeolite in contaminated silica sand. Considering environmental concerns regarding oil-polluted soils, finding novel, safe, and cost-effective oil removal strategies has been critical over the last decade due to international awareness. Ensuring the structural safety of facilities near petroleum industries, especially against earthquake-induced liquefaction, is essential in the civil and geo-environmental field. The existing investigations have primarily studied the stabilization of soils polluted with other contaminants or have concentrated exclusively on chemical stabilization without considering the synergistic consequences of physical adsorption and chemical interactions facilitated by zeolite. There is a lack of extensive experimental proof assessing how natural zeolite impacts the dynamic response of oil-polluted silica sands, particularly concerning liquefaction strength, and whether it could operate as a sustainable option to customary stabilization agents. This paper investigates the consequences of zeolite treatment on the liquefaction response of two types of silica sands (coarse and fine-grained) polluted with crude oil. Zeolite, a natural and environmentally friendly material, was utilized to enhance the liquefaction resistance of silica sand specimens contaminated with oil. This paper investigates the effects of crude oil pollution. It assessed the effectiveness of this eco-friendly stabilizer through simple shear experiments, Fourier-transform infrared spectroscopy (FTIR), and Scanning Electron Microscopy (SEM) analyses. The outcomes indicated that the optimal zeolite content was 6 % for fine-grained sand (124 % increase in liquefaction triggering cycle) and 8 % for coarse-grained sand (154.55 % liquefaction resistance improvement). The FTIR evaluations demonstrated that zeolite treatment enhanced liquefaction resistance by reducing the C-H peak (i.e., the hydrocarbon-related bond). The outcomes relate to the high specific surface area and the porous nature of zeolite particles, which facilitates effective oil adsorption. These findings could assist geo-environmental engineers in selecting this agent as a remediation technique in practice for oil-contaminated sites since zeolite is an abundant and easy-to-use material.