А FOUNDATION DESIGN ON COLLAPSIBLE SOILS: AN INTEGRATED GEOTECHNICAL APPROACH

Collapsible soils are characterized by structural instability and a substantial decrease in stiffness upon wetting, which leads to significant additional settlements under external loading. This behavior introduces considerable uncertainty into foundation design, particularly when the combined effects of wetting and mechanical loading are not explicitly considered within an integrated framework. In this study, a multi-stage experimental methodology was employed, comprising controlled wetting, plate load testing under saturated conditions, and full-scale static load testing of driven piles. This approach enabled the evaluation of soil deformability across multiple scales, ranging from localized stiffness degradation to the overall response of foundation elements subjected to vertical loading. The relationship between the deformation modulus derived from plate load tests and the ultimate load-bearing capacity of piles provided a comprehensive interpretation of foundation performance under conditions of developing soil collapsibility. Based on the integrated experimental analysis, a set of engineering recommendations was formulated, emphasizing the necessity of combining controlled wetting procedures, plate load testing, and full-scale pile testing to ensure reliable foundation design on collapsible soils.