Durability of Galvanized Light-Gauge Steel Shapes

Abstract

This paper reports on the experimental studies on the durability of galvanized light-gauge steel shapes with thickness up to 1.6 mm, inclusive of screw connections. The durability of these shapes and screw connections was examined by cyclic accelerated corrosion tests and shear tests on corroded connections. The test results show that the corrosion rate of shapes depends primarily on the method of galvanizing and that the corrosion rate of Al/Zn-coating (5% aluminum and 55% aluminum) is less than that of common Zn-coating. Also it was clarified that no corrosion of the screwed parts of shapes and screws was observed after the accelerated corrosion test and the shear strength did not decline, even the coating thickness of screws was 5 μm. Thus, according to these test results, the durability of galvanized light-gauge steel shapes was clarified, and from comparison with the data obtained in the conventional outdoor exposure test, the service life of shapes in outdoor application can be estimated.