UCLA

Dust generation is a world-wide issue due to its serious deleterious effects on the environment, human health and safety, and the economy. Although various dust suppression methods have been used for decades, some critical drawbacks in state-of-the-art technology still remain unsolved, such as short-lasting, ground water impact, and prone to water. This work reports a soil stabilizer based on non-toxic material and forms a ductile and durable double-network in soil, namely “D3 soil stabilizer”, which not only improves soil mechanical toughness of surface soil but also suppresses dust generation. A copolymer comprising hydrophilic and hydrophobic components combined with enzyme-induced carbonate precipitation is utilized as an in-situ gelation binder to soil particle. The tunable hydrophobic-to-hydrophilic component ratio minimizes undesirable soil matrix expansion and mechanical strength loss upon experiencing wet-dry processes, while still retains good water affinity. We further demonstrated controllable treatment depth by fine-tuning precursor composition, which is essential to minimize environmental impact. The double-network morphology with carbonate precipitate embedded uniformly in polymer matrix is observed via microscopic imaging. The nature of outstanding ductility, high durability against water, and good long-term stability were supported by systematic unconfined compressive strength (UCS) measurements on treated soil, which show strong inter-particles binding, good retention of peak strength, increased strain at peak strength, and increased toughness after soil samples have experienced wet-dry processes.