Analytical study of the bearing capacity in retaining structures Case of Gasabo District, Gisozi Sector

Abstract

This project addresses the issue of bearing capacity in retaining structures, particularly focusing on how soil properties, retaining wall geometry, and dynamic loads impact the stability and performance of these structures. The problem is rooted in the challenge of designing retaining walls that can withstand external loads while maintaining soil stability, especially in regions with complex soil conditions or seismic risks. The objectives of the study are to analyze the factors influencing the bearing capacity of soil in retaining structures, evaluate the performance of different wall types under various loading conditions, and provide design recommendations for optimal performance. A combination of methods was used to achieve these objectives, including numerical modeling and theoretical analysis to simulate static and dynamic loads on retaining walls. The study employed the Mononobe-Okabe method for seismic load evaluation, alongside experimental validation where necessary. The methodology includes a numerical analysis and theoretical modeling based on the specific soil parameters of the site. For both wall designs: Wall height (H) = 6, Wall thickness at base (B) = 3 m, wall thickness at top (T) = 0.75 m, Density of wall material (concrete) = 24 kN/m³, backfill soil density (γs) = 18 kN/m³, Angle of internal friction of backfill (ϕ) = 30°, Cohesion of foundation soil (c) = 15 kN/m², Angle of internal friction of foundation soil (ϕ') = 28°, Allowable bearing capacity of foundation soil (q_ult) = 200 kN/m², Surcharge load on backfill = 10 kN/m² (due to traffic or buildings) The conclusion emphasizes the importance of incorporating seismic considerations, proper drainage systems, and soil improvement techniques in retaining wall designs, especially in areas with low soil bearing capacity. The study recommends further research on advanced soil- structure interaction modeling and the long-term monitoring of retaining wall performance to improve future designs.