Material characterization of HSS pipes and its effects on the deformation response.

摘要

The design equations for pipelines made of normal grade steel are based on isotropic hardening plasticity model. But, the High Strength Steel (HSS) Pipelines show plastic anisotropy. Stress strain behaviors in the longitudinal and the circumferential directions are different. Thus, it could be erroneous to adopt the same design equations based on isotropic hardening plasticity model for HSS pipelines.;The design problems due to the plastic anisotropy exhibited by the HSS steel have to be solved by finding a suitable material plasticity model that can deal with plastic anisotropy. In this research program, various plasticity models are studied and an appropriate plasticity model is adopted and calibrated to model the plastic anisotropy. The calibrated material model is then used in finite element analysis of deformation response of pipelines. The sensitivity of response of pipeline to the choice of material model is studied for the frost upheaval and local buckling.