Condition Assessment and Repair of Earthquake and Corrosion Damaged Pre-cast, Pre-Stressed Concrete Building Support Piles – A Case History

摘要

This case study describes the assessment and repair of pre-cast, pre-stressed concrete support pilesused to support single story and two-story office buildings in northern California. This paper describeshow it was determined during the assessment that the piles were damaged by an earthquake17 yearsprior to the assessment which resulted in cracks and high levels of chlorides penetrating the pilescausing extensive damage to the embedded pre-stressed wires and vertical reinforcing rods in thepiles to the extent that the piles required extensive repair. As a part of this project a classificationsystem for evaluating the type and extent of damage to the piles was developed along with anappropriate repair procedure for each classification that would be effective in preventing additionalcorrosion damage to the piles for the remaining life of the subject buildings (approx. 30 years).Repairs consisted of a complete rebuild for some while others were coated with epoxy and still otherswere wrapped in a fiberglass sheets layered with epoxy.