Single Row Piles in Integral Bridge Foundations: Challenges and Solutions

This paper presents the challenges and their solutions adopted for the design of two-span continuous integral overbridges supported by single row pile foundations without any interfacing pile cap elements, as part of A14 Cambridge to Huntingdon development. The paper highlights the geotechnical modelling limitations, construction requirements, contractor’s preferences, and other constraints placed on pile configuration due to load demands and form of superstructure. With respect to structural aspects of design, the paper discusses the design challenges and solutions associated with reinforcement detailing within the abutment and pier walls in absence of interfacing pile cap elements. It also touches upon use of strut and tie approach, to propose a safe and buildable detail around the pile reinforcements, and the reinforcements of the substructure element.