Assessment of Paint Layers Quality 3. Analysis by SEM-EDAX and XRF techniques of the paint layers applied on a railway bridge

摘要

In order to identify the premature biodegradation causes of paint applied in 2013 on a railway bridge, top coat layers applied have been investigated by XRF and SEM-EDAX techniques after 32 years, corresponding to periods of operation under identical climatic conditions of 4.5 years and 3.5 years respectively. By analysis of the experimental results obtained, it has been found that by using suitable painting materials (titanium content of about 7.5 % - TiO2 for UV protection) an exploitation period of more than 30 years could be obtained. Low-carbon (low polymer) and titanium dyeing materials with significant content of soluble salts have a low durability and anticorrosive protection capability. They degrade relatively fast both by top coat degradation and by intense increases of biofouling.