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.

世界各地的建筑行业都在使用高能量和碳排放的稳定剂，如水泥，以稳定用于开发土质基础设施的有问题和脆弱的土壤。虽然水泥的加入虽然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使用的前景。为了限制碳排放和保护有限的自然资源，建筑业必须立即寻找合适的水泥和类似材料的替代品来稳定土壤。在最近的过去，有越来越多的兴趣在土木工程中使用生物岩土工程的过程中进行地面改造。生物土工过程使用生物生产的过程或产品进行土壤稳定。生物稳定技术，如真菌和生物聚合物稳定具有巨大的潜力，以取代水泥在土壤稳定，但尚未在文献中进行彻底的研究。在有机基质的存在下，接种到土壤中的真菌物种如糙皮侧耳形成菌丝网络，其引起颗粒聚集并诱导对土壤的斥水性。土壤中的有机基质是控制菌丝网络的生长动力学的关键组分，其总生物量、穿透深度和生长速率都与土壤中的有机基质有关。因此，真菌土壤稳定化的功效直接取决于在将真菌接种到土壤中期间使用的有机基质的类型。另一方面，多糖生物聚合物，如瓜尔胶和黄原胶，当与水混合在土壤中时，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，仅需要少量的生物聚合物来稳定大量的土壤，并且此外，稳定的土壤具有再利用的潜力。然而，当暴露于较长时间的饱和时，生物聚合物稳定的土壤导致水凝胶的部分或完全溶解，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性，有必要确保水凝胶可以对水入侵具有弹性。考虑到生物聚合物可以作为菌丝网络生长的基质，而真菌可以诱导对土壤的拒水性，确保水凝胶可以保持稳定以抵抗水侵入，当这些方法协同作用时，可以解决两种生物稳定技术的需求。考虑到各种各样的真菌物种和生物聚合物，真菌和生物聚合物之间的独特的协同作用，建议在这项研究中进行优化设计。该研究的结果将导致开发一套真菌-生物聚合物组合作为土壤稳定剂。此外，研究结果可以使现场工程师以不同的方式修改水泥不能执行的地面，从而在地面改善中带来新的机会。