Investigation of corrosion effect on bolted and welded connections in steel structures

Steel structural systems are preferred structural systems due to their high bearing capacity and ductile behavior. Structural properties of steel structural elements made of steel material which have undergone a good control during the production phase can be damaged by time due to various environmental effects. Corrosion damage is one of the most important of these harmful effects which may cause deterioration of the steel structure elements. Corrosion can be inevitable in steel structural systems under environmental effects. Damage due to both physical and chemical changes of corrosion becomes even more important. It is important to know the mechanism of corrosion to be protected from corrosion. In the event of the possibility of corrosion damage and not taking into account the effects on the structure, renewal and maintenance can be laborious and expensive. In this thesis, steel members of different thicknesses (4 mm and 6 mm) in S235 grade steel and in different types of joints (bolted, butt welded and fillet welded) were corroded and tested under the effect of axial tensile force. Changes in the behavior and axial tensile load bearing capacity observed as a result of corrosion damage in steel test elements were investigated. As a result of the experiments, the lowest decrease in the strength values compared to the non-corrosion reference specimen with the corrosion of the steel material was observed as 3% in the 6 mm-thick bolted joint plates with artificial corroded bolts and the highest reduction was observed by 37% in the sample with only 6 mm thick bolt-jointed plates and changes in material properties. As a result of the corrosion, it was observed that the decrease in tensile strength and the changes in the plates were not linear despite the linear loss of the material.