MECHANICAL BEHAVIOR AND MICROSTRUCTURE OF CRUDE-OIL-POLLUTED STRUCTURAL LOESS IN NANJING CITY, CHINA

In the exploration, processing, and storage of oil, oil leakage accidents often occur. However, most organic oil pollutants are difficult to degrade. When oil pollutants permeate and invade the soil, the mineral composition and structural characteristics of the soil change. Furthermore, such changes alter the engineering mechanical characteristics of the soil layers, causing differential settlement of oil field buildings or structures and oil waste storage yards. Indeed, structural evolution is the core reason for changes in field soil engineering characteristics. There has been a serious shortage of studies on the structural evolution and mechanical behavior of organic contaminated soil. Therefore, it is necessary to conduct research on soil structure evolution and mechanical behavior under the coupling of oil organic pollutants and stress. In this study, for structural loess affected by different degrees of crude oil pollution, the strength characteristics and seepage properties of undisturbed loess contaminated by crude oil pollution at different stress loading states were determined by conducting triaxial consolidation-undrained shear and penetration tests. Based on nuclear magnetic resonance (NMR) and laser particle size tests, structural characteristic parameters, such as pore characteristics and particle size, are discussed under the condition of crude oil pollution, corrosion, and stress loading, which provides important evidence for the assessment of soil damage in oil pollution fields.