Combined Load and Displacement Controlled Testing to Support Development of Simplified Component Design Rules for Elevated Temperature Service

Combined load and displacement controlled test results are being used to develop and verify a simplified component design methodology for elevated temperature service. A key feature of the proposed design methodology is the use of rules for the evaluation of strain limits that are based on the application of elastic-perfectly plastic (EPP) analysis method with a pseudo yield stress to bound component response to applied loadings. The resulting strain ranges would then be used as input to the evaluation of creep-fatigue damage. This paper describes testing with two separate servo-hydraulic machines that are electronically coupled in parallel to represent combined loading effects on a two-bar test configuration.