Invasive Probing and Visual Observations

There are no direct, nondestructive means to assess the condition of post-tensioning (PT) systems. The most direct way of examining tendon condition is to conduct selected probing at the anchorages, couplers, and other strategic locations along the tendon trajectory.

Visual observations were conducted at select probe openings of the post-tensioning system to document conditions. This included documentation of signs of corrosion of PT components, prestressing wire pitting, degradation of the “sisal craft” paper used for the tendon duct, and condition of the corrosion-protection mastic. Photographs were made to document conditions, and where appropriate, measurements were taken of pertinent details such as cover depth.