Latest Highway Bridge Spread Footing Research Findings in Ohio

Abstract

Shallow foundations are more economical than deep foundations and are utilized to support many different types of structures in our society. However, one type of structure to which shallow foundations have not seen widespread applications in Ohio and elsewhere is highway bridges. This may be because most bridge engineers question shallow foundation’s ability to maintain adequate load-carrying capacity in all environments. The research team at Ohio University continued its study of shallow foundations at highway bridge construction sites in Ohio. At one of these sites, A-2-4 and A-3a soil types were encountered in a borehole. The central pier footing was instrumented with sensors and monitored during construction. The field instrumentations consisted of multiple sensors and stations for recording contact soil pressure under the footing, settlement of the footing, and tilting of pier columns tied to the footing. A USGS quality bench mark was incorporated to establish a solid permanent bench mark at the site. The field performance data collected in the study provided further insights into how contact soil pressure, footing settlement, and columns/wall tilting were correlated with each other throughout various construction stages. The study also produced outcome on general reliability of a settlement prediction methods outlined in the AASHTO LRFD Design Specifications.