Rational design solutions for deep excavations using soil nail wall systems

Purpose. The study aims to optimize the design and reduce soil nail length in deep excavations with a soil nail system in fast-draining soils. Additionally, it investigates the parameters influencing slope stability in fast-draining soils. Methods. Integrating field and lab data with soil nail properties and advanced modeling, this study investigates how fixed nail length, inclination and spacing affect the stability of a 20 m-deep excavation in fast-draining soil. Findings. The study findings reveal that optimal parameters, such as nail spacing and inclination angle, have been identified for reinforcing deep excavation walls, ensuring stability with minimal nail length. Notably, the stability of excavation walls can be achieved without the need to increase the length of the soil nails. The recommended parameters are characteristic of an 8-meter-long soil nail system, a 30-degree inclination angle, and a spacing of 1.5×1.5 meters. Originality. This study presents a novel perspective on the structural characteristics of soil nails by determining emphasizing nail spacing, inclination angle, and fixed nail length. It offers a comprehensive framework for designing soil nail walls in fast-draining soils during deep excavations, contributing to advancements in open-cut excavation practices. Practical implications. The study offers practical implications for designers involved in deep slope earthworks, enabling the development of efficient and rational design solutions that ensure excavation stability and prevent displacement during excavation while reducing costs and project duration.