Ultrasonic tomography of grouted duct post-tensioned reinforced concrete bridge beams

摘要

Some concern exists over the safety and durability of the 600 post-tensioned bridges in the UK, and the much larger number worldwide. The objective of the work reported herein was to identify voiding in the metallic tendon ducts in these bridges. Voiding can give rise to two Sets of problems; (a) possible ingress of chlorides, which would cause corrosion; and (b) a lack of redistribution of stress within the beam. It Was against this background that it was important to first of all identify the extent of voiding in post-tensioned bridges.