Numerical investigation of the static behavior of stepped soil nail walls

This paper presents a numerical investigation on the static behavior of stepped soil nail walls constructed in dry sandy soils. The finite element method was used to study influence of wall geometry and soil parameters on behavior of the walls. We analyzed walls with heights of 10, 15, and 20 m .This study shows that the wall deformation and the nail tensile forces of the stepped soil nail wall are smaller than those of the typical soil nail wall. If properties of soils such as friction angle, cohesion, and elastic modulus decrease, these will result in more decrease in the wall lateral displacement and nail tensile forces of a stepped soil nail wall. Therefore, stepped soil nail walls are more effective in soft soils than hard soils. When a step is located at the middle of the wall height, the wall lateral displacement and nail tensile forces are minimized; hence, the ratio of the optimal step depth to the wall height is 0.5. As the step width increases, the wall deformation and nail forces decrease. Numerical analysis demonstrates that the minimum step width is approximately 0.1 times of the wall height.