Fatigue Cracking in Welded Steel Structures

Structural reliability is often evaluated using probabilistic-based methods since variations can occur in the loading, material behavior, and composite structural performance over time.

The intent is to establish the probability that a structural condition could develop and then evaluate the risk relative to the cost for prevention. One application of these methods is life-cycle costing, which determines the optimal time for replacement of structures or components rather than continued maintenance costs and operational safety risk.

Failure of Welded Connection of Cannelton Control Valve

Reliability Evaluation of Fatigue Cracking at Welded Connection

ANATECH, a Structural Integrity Associates company has performed analyses to determine the fatigue cracking performance of welded connections in hydraulic steel structures. These analyses use global modeling to determine the cyclic demands on the welded joint, local modeling to establish the residual stress distributions due to welding, and then evaluate the fatigue growth of cracks under cyclic loading. This methodology has been incorporated into U. S. Army Corp of Engineers Guidance for ETL 1110-2-556, Advanced Reliability Analysis of Fatigue Cracking in Horizontally Framed Miter Gates.