ABSTRACT
Based on the author’s long experience, implementing suitable state-of-the-art non-destructive testing techniques in condition evaluation of post-tensioned bridges’ invisible prestressing system is an essential approach for ensuring post-tensioned bridges’ safe usage, long time durability and appropriate level of asset management. It also assists in determining the remaining service life of those bridges. There are thousands of aging post-tensioned bridges getting close the end of their service life. Due to reasons like environmental stresses, construction and maintenance faults the safe usage of bridges may be uncertain or even dangerous. In extreme cases this may lead even to sudden collapses of bridges.
Applying NDT techniques in post-tensioned bridges enables evaluation of the prestressing system grout injection, which is critical for the system durability and functionality. The introduced NDT techniques, ultrasound tomography and Impact-Echo, used together with slightly invasive investigations assist in this important evaluation.
