Review of methods to enhance the geotechnical and structural capacity of existing footings

Abstract

Enhancing and retrofitting existing structural components is a critical process that aims to restore or improve the performance, safety, and durability of constructions. Foundations in particular can be susceptible to damage, failures, or differential settlements for a number of different reasons, including improper design parameters, lack of soil investigations, additional weights produced by story extensions, lateral loads resulting from seismic events, or changes to the structure’s purposes post-construction. Thus, the need for effective and economic strengthening methods is essential. Available techniques used to increase the structural and geotechnical foundation capacity are discussed in detail in this review paper. The geotechnical underpinning techniques involve soil improvements by piling, micro-piling, grouting, helical piers, and geosynthetic reinforcements, as well as structural enhancement approaches including concrete jacketing and footing enlargement. In terms of geotechnical improvement, micropiles were found to be the most effective in enhancing and stabilizing the foundation, and helical piers were the fastest and easiest to install in the soil. On the other hand, enlarging the footing offered better load distribution and enhancement to the shear capacity.