Department head, Industrieanlagen-Betriebsgesellschaft (IABG), Ottobrunn, Einsteinstrasse 20,
Pages: 14 Published: Jan 1989
After a short historical introduction, the reasons why standardized stress-time histories are necessary and useful are given. A standardized stress-time history must be based on several, preferably many, stress measurements in service. It must also be a fixed stress sequence, not just a spectrum for which an infinite number of stress-time histories are possible. It must be based on a cooperative effort of several competent laboratories, preferably from different countries. It must also be generally applicable to the structure or component in question. The truncation or omission levels, if any, must be clearly stated and must be substantiated by tests. A reasonable return period or block length must be also selected. Preferably, standardized stress-time histories should be used for: 1. comparison of materials, production processes, and design details as well as cooperative (round robin) test programs; 2. investigation of the scatter of fatigue life; and 3. producing preliminary fatigue design data for components etc.; if the service loads on the component in question are of variable amplitude.
Five standardized stress-time histories available at present (Twist, FALSTAFF, Gauss, Helix-Felix, and Cold TURBISTAN) are briefly described as well as the six at present in progress (WASH, WALZ, WISPER, ENSTAFF, Carlos and hot TURBISTAN).
fatigue strength under variable amplitudes, standardized stress-time histories, truncation and omission levels, fatigue (materials), testing, fatigue testing
Paper ID: STP10346S