Fungi-Biopolymer synergistic application in soil stabilisation

真菌-生物聚合物在土壤稳定中的协同应用

• 批准号: EP/Y002202/1
• 负责人: Sravan Muguda Viswanath
• 金额: $ 21.07万
• 依托单位: Durham University
• 依托单位国家: 英国
• 项目类别: Research Grant
• 财政年份: 2024
• 资助国家: 英国
• 起止时间: 2024 至 无数据
• 项目状态: 未结题
• 来源: https://gtr.ukri.org/projects?ref=EP%2FY002202%2F1
• 关键词: Fungi; Biopolymer; synergistic; application; soil

Construction industries worldwide use high-energy and carbon-emitting stabilisers like cement to stabilise problematic and weak soils used in developing earthen infrastructure. Whilst the addition of cement though has improved soil strength and durability, it causes a significant environmental impact on the ground and reduces the prospects of soil reusability. To limit carbon emissions and conserve limited natural resources, it is pivotal for the construction industry to immediately seek suitable replacements for cement and similar materials for soil stabilisation. In the recent past, there is a growing interest in civil engineering to use bio-geotechnical processes for ground modification. Bio-geotechnical processes use biologically produced processes or products for soil stabilisation. Bio-stabilisation techniques like fungi and biopolymer stabilisations have huge potential to replace cement in soil stabilisation but have not been thoroughly investigated in the literature. Fungi species like Pleurotus ostreatus on inoculation to soil in presence of organic substrate form hyphal networks which cause particle aggregation and induce water repellency to the soil. The organic substrate in the soil is the crucial component which controls the growth kinetics of the hyphal network concerning its total biomass, penetration depth and growth rate. Thus, the efficacy of the fungi soil stabilisation is directly dependent on the type of organic substrate used during the inoculation of fungi into the soil. On the other hand, polysaccharide biopolymers like guar and xanthan gums when mixed in soil with water form three-dimensional porous structures called 'hydrogels' that interlink soil particles and improve soil strength and durability. Only small quantities of biopolymer are required to stabilise large quantities of soil in comparison to cement and further, the stabilised soil has potential to be re-used. However, biopolymer-stabilised soils when exposed to longer periods of saturation lead to the partial or full dissolution of hydrogels causing a reduction in soil strength. To ensure effective biopolymer soil stabilisation, it is necessary to ensure the hydrogels can be made resilient against water intrusion. The needs of the two bio-stabilisation techniques can be addressed when these methods are in synergy considering biopolymer can act as a substrate for hyphal network growth, while the fungi can induce water repellency to the soil ensuring hydrogels can remain stable against water intrusion. Considering the wide variety of fungi species and biopolymers available, the distinctive synergy between fungi and biopolymers is proposed to be optimally engineered in this study. The outcomes of the study will lead to the development of a suite of fungi-biopolymer combinations as soil stabilisers. Further, the findings can enable field engineers to modify ground in different ways which cement cannot perform leading to newer opportunities in ground improvement.

世界各地的建筑业都使用水泥等高能和碳排放稳定剂来稳定开发土质基础设施时使用的问题土壤和软弱土壤。虽然水泥的添加提高了土壤的强度和耐久性，但它对地面造成了重大的环境影响，并降低了土壤可重复利用的前景。为了限制碳排放并保护有限的自然资源，建筑行业立即寻找合适的水泥和类似材料的替代品来稳定土壤至关重要。近年来，人们对土木工程利用生物岩土工艺进行地面改造的兴趣日益浓厚。生物岩土工艺使用生物生产的工艺或产品来稳定土壤。真菌和生物聚合物稳定等生物稳定技术在土壤稳定方面具有替代水泥的巨大潜力，但尚未在文献中进行彻底研究。平菇等真菌物种在有机基质存在下接种到土壤中形成菌丝网络，引起颗粒聚集并诱导土壤防水。土壤中的有机基质是控制菌丝网络生长动力学的关键组成部分，涉及其总生物量、渗透深度和生长速率。因此，真菌土壤稳定的功效直接取决于将真菌接种到土壤中时使用的有机基质的类型。另一方面，瓜尔胶和黄原胶等多糖生物聚合物在土壤中与水混合时，会形成称为“水凝胶”的三维多孔结构，使土壤颗粒相互连接，提高土壤强度和耐久性。与水泥相比，只需少量的生物聚合物即可稳定大量的土壤，而且稳定的土壤具有重复利用的潜力。然而，生物聚合物稳定的土壤当暴露于较长时间的饱和状态时，会导致水凝胶部分或完全溶解，从而导致土壤强度降低。为了确保有效的生物聚合物土壤稳定，必须确保水凝胶能够抵抗水的入侵。当这些方法协同作用时，这两种生物稳定技术的需求就可以得到满足，考虑到生物聚合物可以作为菌丝网络生长的基质，而真菌可以诱导土壤的防水性，确保水凝胶可以保持稳定，防止水侵入。考虑到可用的真菌种类和生物聚合物的种类繁多，本研究建议对真菌和生物聚合物之间独特的协同作用进行优化设计。该研究的结果将导致开发一套作为土壤稳定剂的真菌-生物聚合物组合。此外，这些发现可以使现场工程师能够以水泥无法实现的不同方式修改地面，从而为地面改良带来新的机会。