Behavior of Hybrid Mechanically Stabilized Earth Walls Subjected To Traffic Loadings

Abstract

The view of the new leadership in Saudi Arabia, as outlined in 2030 Vision, is to go in a clear direction to adopt the recent and advanced developments and technologies in all fields. All the government agencies and sectors have been trying to go along with this vision in all infrastructure projects in order to contribute to the achievement of the sustainable economic plans in the country. Qassim University was keen to hold with the direction of the Saudi leadership through the educational approach of research and scientific courses to strengthen the concept of the 2030 Vision for students and society. One of these technologies is Mechanically Stabilized Earth Walls. This technology is somewhat new in the Saudi construction market. Therefore, a study to investigate the behavior of these walls was the need of time in order to obtain a safe and optimal structural design, as the cases of collapse of this type of walls still exist, especially in the case of changing the engineering dimensions of the wall and mechanical properties. Mechanically Stabilized Earth walls (MSEW) have been showing improved performance and acceptance level among engineers and contractors recently particularly when used to widen roads to accommodate large traffic or as ramps for bridges. MSEWs have a number of advantages over traditional reinforcement concrete walls; they can reach more heights at a reasonable cost. The need for higher retaining walls requires the tendency for new techniques. One of such techniques is the use of large geogrid spacing. In such a case, there is a number of solutions such as the use of wire mesh to prevent local failure at the face of the wall due to the large spacing. Our aim in this research is to study the behavior of MSE walls with various forms of reinforcement in bridge abutments under traffic loading using numerical. Several cases related to the behavior of the Mechanically Stabilized Earth Walls were studied including the change of the friction angle of the reinforced fill soil and the study of the influence of loads on the MSEW as well as the change of the geogrid properties. The results of these cases were discussed, including the results of the tensile forces in the geogrid and the wires mesh, the vertical and horizontal displacement of the facing wall and finally shear strain increment. Results show that the maximum tensile force in the geogrids increases as the strength of the soil is reduced by decreasing the friction angle. The maximum tensile force in the geogrid varies with the geogrid vertical position within the wall. Rankine failure surface angle with the facing panels increases as the friction angle decreases. The maximum tensile force in the geogrid was found at around one-third of the wall height. The horizontal displacement in facing of the wall decreases with increasing friction angle. With traffic loads placed above the wall, the tensile forces in the geogrid and wires were not affected due to the increased friction angle.