DETECTING DETERIORATION IN ASPHALT-COVERED BRIDGE DECKS

Abstract

Information on the condition of bridge decks is required for reasons of safety and to develop a comprehensive program of maintenance, rehabilitation, and replacement. Where the deck has a bituminous surfacing, detecting deterioration in the concrete slab presents serious technical difficulties. In many cases, existing procedures are not adequate to produce reliable information. This paper reports the technical and economic evaluation of the following test techniques: chain drag, sonic reflection, ultrasonic transmission, microseismology, resistivity, electrical potential, radar, and thermography. All of the techniques were investigated under controlled conditions at a full-scale test site. The results were compared with the criteria devloped for an ideal test method. Radar and thermography were found to have the most potential for development into routine operational procedures for detecting deterioration in asphalt-covered bridge decks. Also, additional development work needed was identified. (Author)