STRESS MEASURMENT FOR THE BRIDGE SUSPECTED OF FATIGUE DAMAGE

Abstract

  Cracks suspected of fatigue damage were found at the welded connection part at which a vertical member penetrates the steel deck in the single rib lohse bridge. Causes of these cracks are probably related to welding or fatigue problem and appropriate measures must be taken especially for the fatigue damage. This study presents the cause identification of the damage and crarifies its mecahism. By investigating a core taken from the cracked part, an unwelded zone were found in the root of weld and the break surface showed a similar face caused by fatuge damage. The stress measurement clarified the effects of live loads on the damaged part, with forcusing on the level of live loads and their loading positions.