The impact of water repellency on soil mechanics

与岩土工程中的普遍假设相反，土壤可以表现出低润湿性。在污染的、工程化的和天然的土壤和废物中已经确定了斥水行为。这些包括石油污染的土壤（如炼油厂的石油泄漏）、富碳废物（如褐煤矿废物）、碳工程土壤（如用生物炭改良的土壤）、遭受野火的土壤和一些农业和森林土壤，以及矿物勘探中的硫块。尽管对水文影响进行了研究（减少渗透，风和水对土壤侵蚀性的增强，火灾后泥石流），但对拒水性对土壤工程性质的影响知之甚少。该提案将通过调查润湿性与非饱和土壤（孔隙中有空气和水）的工程性质之间的关系来解决这一知识空白。它将测试的假设，具有较低的亲水性的土壤表现出较差的性能方面的工程行为（较高的压缩性和较低的剪切强度）。这将通过结合土壤科学，化学和土壤力学的实验技术来实现。结果将提供第一次深入了解润湿性对土壤的工程行为的影响。

Contrary to a prevalling assumption in geotechnical engineering, soils can exhibit low wettability. Water repellent behaviour has been identified in contaminated, engineered and natural soils, and waste. These include oil contaminated soils (e.g. oil spills in refineries), carbon rich waste (e.g. lignitic mine waste), carbon engineered soils (e.g. soils amended with biochar), soils subjected to wildfires and some agricultural and forest soils, and sulphur blocks in mineral exploration. Despite research on the hydrological implications (reduced infiltration, enhancement of soil erodibility by wind and water, post fire debris flows), very little is known on the influence of water repellency on soil engineering properties. This proposal will address this knowledge gap by investigating the relationship between wettability and the engineering properties of unsaturated soils (with air and water in the pores). It will test the hypothesis that soils with a lower affinity for water exhibit poorer performance in terms of their engineering behaviour (higher compressibility and lower shear strength). This will be achieved by combining experimental techniques from Soil Science, Chemistry and Soil Mechanics. The results will provide a first insight into the influence of wettability on the engineering behaviour of soils.