Cone Penetration Test Sounding and Pile Driving

Hurricane Katrina severely damaged the I-10 Twin Span Bridges in New Orleans, Louisiana. Because these bridges are the primary evacuation route for the City of New Orleans, the design of the replacement bridges had to be done within a short time frame. The pile foundation of the bridges was designed with limited soil borings and cone penetration test (CPT) soundings, which resulted in a large amount of pile cutoff and potential undesirable pile buildups. The Louisiana Department of Transportation and Development (DOTD) was able to perform additional CPT soundings to define the soil conditions better during construction. Using these additional data, the Louisiana DOTD geotechnical engineer produced a more reliable design and avoided potentially costly construction claims. The problems encountered during construction and the improved pile foundation design are documented.