Iowa Statewide Urban Design and Specifications

About the research

The main objective of this research was to investigate the efficacy of the use of helical pile foundations for accelerated bridge construction (ABC) projects. The focus of the research was helical pile use to accelerate foundation construction on bridge projects.

The capacity of helical piles is on par with several other deep foundation technologies. Installers tout the simplicity and speed of installation, along with the ability to work within areas of limited size with smaller equipment. The required equipment for installation (skid steer, backhoe, or excavator) lends itself to quick deployment and being an economical solution (i.e., excavator vs. crane), an advantage for any bridge project, but particularly for low–volume roads where budgetary considerations tend to be a specific priority.

This report includes details on the current state–of–the–practice for helical piles, the potential adoption of helical piles for ABC projects, other key project considerations, and recommendations for further study/research.

This report includes a literature review, contractor/installer questions and answers, a cost comparison, and images from a helical pile installation demonstration. It also provides a decision making framework, which includes two tools: a process flowchart of questions and answers and a table matrix of questions and considerations categorized by site and constructability, geotechnical, and design. The References section includes a list of webinar resources at the end of it