LARGE DIAMETER HELICAL PILES FOR REFINERY EXPANSION

摘要

A refinery expansion project for Marathon Petroleum Company in Southern Louisiana required existingrnmedium to large pipe racks to be expanded for additional capacity. Foundation modifications werernnecessary in order to add levels to the existing pipe racks. New piles were added and existing pile caprnfoundations were expanded. Several different pile types were considered. Custom designed large diameterrnhelical piles were chosen, because they can be installed quickly with low overhead restrictions, producernminimal soil spoils, and are cost effective. The load capacity required for piles was higher than typical,rnoff-the-shelf helical piles. In particular, the lateral load capacity demand was high due to wind loads of arnhurricane prone region. Methods used to design and size helical piles are summarized including capacityrnto torque ratio estimation for composite helical piles. Pile load testing was performed in order to confirmrndesign capacities of the helical piles under axial and lateral loading. Measured axial and lateral deflectionsrncompared well with predicted values. This case history evaluates the effectiveness of modern helical pilerndesign methods within the context of a real and practical example.