Influence Charts for Bearing Capacity and Numerical Modeling of Embedded Footings on Silty Sand
摘要
This research examines the bearing capacity of shallow footings placed on silty sand in the Plai Phraya District, Krabi Province, Thailand. Through a combination of laboratory testing, finite element modeling (FEM), and sensitivity analysis. Fundamental geotechnical properties such as soil cohesion (c), friction angle (ϕ), unit weight (γ), and geometry parameters were analyzed to assess their influence on the bearing capacity of shallow foundations. Based on these analyses, the study developed influence charts for square and rectangular footings, providing a practical framework for engineering design. The sensitivity analysis identified friction angle and soil cohesion as the most critical factors in enhancing bearing capacity, while geometric factors like footing width and embedded depth had a less pronounced impact. FEM simulations, using load increments of 654 kN/m2, revealed a total settlement of 7.24 mm and a maximum bending moment of 15.26 kN m/m, which informed the reinforcement design of the shallow footing. The results align with ASTM D1194-94 standards, confirming that the foundation remains stable under the expected load conditions (a total settlement not greater than 25 mm). These findings offer a practical tool for engineers working on shallow foundation projects, particularly in complex soil environments. The Influence charts provide a visual and numerical guide for estimating allowable bearing capacity based on specific soil conditions and foundation geometries, helping to ensure safe, efficient, and cost-effective designs. The insights from this study can significantly enhance foundation performance in regions with sandy soils, promoting more informed engineering practices in foundation design and construction.