Definitions of stresses and strains Sample Clauses

Definitions of stresses and strains. Global strain refers to the strain distribution from a uniform cross section at a section beyond the zone of influence of any discontinuities. Local strain includes the contributions from all loads including residual stress, strain concentration and thermal strain. Stress is in general defined as first principal stress (maximum acting tension stress). Strain is in general defined as first principal strain (maximum acting tension strain). When local stress distributions are determined by FEA local strain is the peak strain occurring at the external surface exposed to CP. The global strain may be determined as the peak value of the linear strain distribution due to the same cross sectional axial force and bending moment. This is illustrated in the figure below. NOTE Linearization is dealt with in more detail in ASME VIII, division 2, Appendix 4. Figure showing the principle of linearization. The actual stress distribution through the wall thickness is represented by solid lines. The global stress distribution may be determined by linearization defining the stress distribution shown with a dashed line.