Assessment of the Pseudo-static seismic behavior in the soil nail walls using numerical analysis

The suitable performance of nail walls during strong ground movements as well as flexibility than to other guard structures such as retaining walls makes it more evident that this system should be examined under earthquake effects. Therefore, it is essential to study the factors affecting the stability and deformation of the reinforced walls by the nailing method under seismic conditions. In the present research, using the finite element method, the performance of the restrained wall by nailing method and with a height of 10 m, using Pseudo-static seismic analysis has been investigated. Then the influence of the factors such as length, angle, the distance between the nails, the horizontal seismic coefficient (K_h), and the construction stages progress on the maximum wall lateral deformation, the safety factor and the maximum force in nails have been investigated. According to the most important results, placing nails with an angle between 10 and 15 degrees has the lowest displacement, and the maximum safety factor in static and the Pseudo-static numerical analysis, and the nails will have the best performance. In addition, by increasing nails' length, the maximum wall lateral deformation and the maximum force in nails decrease, and the safety factor will increase. As well as by increasing the nails' horizontal and vertical distance from each other, the maximum wall lateral deformation and the maximum force in nails increase, and the safety factor will reduce. Also, the results revealed that by increasing the nails' normal stiffness (EA) located on the trench wall, the share of the resistant tensile force created in the nails from the total active force acting on the wall increase as a result, the maximum wall lateral deformation in the soil nail wall will decrease, and the maximum force created in the nails and the safety factor will increase. Also, the results show that by increasing the construction stages progress and horizontal seismic coefficient (K_h), the safety factor reduce, and the maximum force in nails and the maximum wall lateral deformation will increase. Also, based on the findings from this research, the results obtained from the Pseudo-static seismic analysis (such as the maximum lateral deformation of the wall and the maximum force in the nails) are more than the static analysis. Conversely, the safety factor obtained from the Pseudo-static seismic analysis is less than the static analysis.