Extensive efforts have been made to resist topsoil instability by enhancing the inter-particle cohesion for the loose structure and weak cohesion of natural sand. In this study, considering the ecological and environmental aspects, an eco-friendly composite material, namely, a hydrophilic polysaccharide biopolymer (HPB) binder, was employed for the topsoil stability. A series of laboratory tests and numerical simulations were conducted to explore the properties and cohesion mechanism of modified sand. The results indicated that the HPB could significantly improve the mechanical properties of the natural sand due to the strong inter-particle bond offered by the network membrane structure. The anti-erodibility of the modified sand was improved, and a capacity to resist erosion of the topsoil by the combined effects of surface covering, strong intergranular bonding connections, and tiny pore throats was observed. This binder provided an appropriate environment for vegetation growth and significantly decreased the erosion rates after vegetation was established. The modified slopes maintained long-term stability by the integrated system of the sand- biopolymer matrix and plant matter. This research can help in the analysis and application of modified technology to control topsoil failure..

针对天然砂的松散结构和弱内聚力，通过增强颗粒间的内聚力来抵抗表土不稳定性已经做出了广泛的努力。在这项研究中，考虑到生态和环境方面，一种环保复合材料，即亲水性多糖生物聚合物（HPB）粘合剂，被用于表土稳定性。进行了一系列室内试验和数值模拟，以探索改性砂的性质和凝聚机制。结果表明，由于网状膜结构提供的强颗粒间结合，HPB可以显着改善天然砂的力学性能。提高了改性砂的抗侵蚀能力，通过表层覆盖的综合作用，抵抗表土侵蚀的能力，观察到强烈的晶间键合连接和微小的孔喉。这种粘合剂为植被生长提供了适当的环境，并显着降低了植被建立后的侵蚀率。改良后的斜坡通过沙-生物聚合物基质和植物物质的综合系统保持长期稳定性。本研究有助于分析和应用改良技术来控制表土破坏。