Using Advanced Technologies to Assess Deterioration in Concrete Bridge Decks

Abstract

Bridges throughout the nation are continuously deteriorating, and current improvement efforts have not been sufficient for closing the investment gap. Without investing in bridge condition today, the structural integrity of the bridges, as well as the comfort, cost, and most importantly safety of motorists is compromised. During routine bridge deck inspection, simplistic methods for assessing deterioration in concrete bridge decks are substandard and only capable of detecting deterioration in its moderate to severe stages. To provide a more thorough assessment of deterioration in concrete bridge decks, advanced technologies should be incorporated into bridge inspection. Using advanced technologies like surface roughness and ground penetrating radar, deterioration hidden from the naked eye or missed using traditional assessment methods can be more accurately detected, evaluated, and reported. When accurately reported, present condition can be compared to past condition to determine what improvement efforts should be made and when. Maintaining bridges in good condition presently is more cost-effective than rehabilitating or replacing bridges in poor condition in the future. This study aims to demonstrate that a more thorough assessment of surface and subsurface deterioration in Rhode Island concrete bridge decks can be obtained through the use of advanced technologies like surface roughness and ground penetrating radar. Three Rhode Island concrete bridge decks, visually in good, moderate, and poor condition, are initially tested to generate surface and subsurface deterioration maps, then tested a second time 2 years later (the length of time of a typical routine bridge inspection) to study the change in subsurface condition over time. Both initial and secondary findings are compared to reported bridge inspection deck conditions to assess accuracy in reported bridge deck condition. The subsurface conditions of the original test in 2015 will be compared to those of the secondary test in 2017, to determine change in subsurface condition over time using mean attenuation. Change in mean attenuation over time allows for the determination of rate of deterioration without the need for corroborative testing and without using a deterioration threshold. It is important to obtain a full picture of surface and subsurface deterioration, to determine rate of deterioration, and to accurately report findings during routine bridge inspection, to best determine what management strategies should be implemented and when, for preservation purposes.