Foundation Settlement Due to Soil Bearing Capacity Limitations

Abstract

The serviceability and long-term stability of any structure are fundamentally dependent on the performance of its foundation and the underlying soil. This research provides a geotechnical analysis of foundation settlement as a direct consequence of soil bearing capacity limitations. The study differentiates between two primary failure criteria: shear failure (the ultimate bearing capacity, or q_ult and excessive settlement (the allowable bearing capacity, or q_ult. While shear failure represents a catastrophic collapse, settlement is a serviceability issue that can cause significant structural damage, such as cracking and tilting. This paper analyzes the mechanisms by which settlement occurs when applied foundation loads are within the safety factor for shear failure but exceed the pressure that the soil can sustain without undue deformation. The analysis focuses on cohesive soils, where long-term consolidation settlement is often the governing design factor, and on granular soils, where immediate elastic settlement must be controlled. Using standard geotechnical methods, this study demonstrates that the allowable bearing capacity is frequently dictated by settlement criteria rather than shear criteria, confirming that a settlement analysis is an indispensable component of safe foundation design.