The discussion revolves around the calculation of allowable stress for different materials, particularly in the context of mechanical and civil engineering applications. Participants explore methods for calculating allowable stress, relevant codes, and the implications of factors such as safety and material properties.
Participants express differing views on the availability of resources for allowable stress calculations, with some asserting that specific codes are necessary while others provide general guidance on stress criteria. The discussion remains unresolved regarding the best approach to obtain detailed calculations and the specific codes applicable based on geographic location.
Participants highlight limitations related to the specificity of codes required for different regions and applications, as well as the potential inaccessibility of proprietary resources.
Q_Goest said:Hi araan.
Allowable stress is a term used to indicate the maximum amount of stress a material may be subjected to given a predetermined factor of safety. In mechanical engineering, we use allowable stress in piping and pressure vessel analysis. I believe civil engineering uses this concept for other purposes as well, including reinforced concrete structures.
Regardless of its use, the calculation of stress can be done using any method suitable, such as conventional hand calculations, using Roark, ASME code calculations, FEA, etc... The stress obtained from those calculations must then be compared to the maximum stress the material is allowed to be exposed to (ie: the allowable stress). For piping codes for example, the stress determined by calculation may not exceed 2/3 of yield strength or about 1/4 of ultimate tensile strength, depending on the code.