Analysis of Digital Images During the Assessment of the Results of the Pull-Off Adhesion Tests During the Coating Evaluation of the Fernando Espinosa Bridge

摘要

The Fernando Espinosa Bridge is one of the largest steel bridges in Mexico; it is located in the western state of Jalisco, and is of particular importance since it is a strategic way linking the city of Guadalajara (third largest city in Mexico) with Mexico City. For a recent rehabilitation project the conditions of the existing coating system was evaluated to determine the extent of the work that needed to be done. This evaluation involved several techniques that included pull-off testing. Additionally, the evaluation involved a system of patch tests in order to do an on-site evaluation of several coating systems, which were also tested by the pull-off adhesion test method. For the evaluation of the adhesion tests, three methods of digital analysis of the images were used and compared in order to help identify the results of the test and the location of the failure. The results obtained from the digital analysis of the images were also helpful to establish a very precise statistical method that helped quantify the percentage of failure observed after each adhesion test. This work details the evaluation performed on the bridge structure and the implementation of digital image analysis to help quantify the results of the pull-off adhesion tests.