Critical Strain Based Ductile Damage Criterion and its Application to Mechanical Damage in Pipelines
Strain based assessment of mechanical damage in pipelines requires a failure criterion for cracking based on plastic damage. Several criteria have been proposed by industry codes such as B31.8 and in the literature. However, these criteria essentially are based on engineering decisions. In this paper, a plastic damage based criterion that combines material critical strain and triaxiality of stress is used. The theoretical aspect of the criterion, including early work by Hancock and Mackenzie on strain limit (i.e., reference failure strain), ? f, for ductile failure is discussed. The experimental aspect of materials critical strain and its measurement using uniaxial tensile testing is described. An elastic-plastic finite element analysis is employed to calculate ductile failure damage indicator (DFDI), which can be used to describe the amount of accumulated plastic strain in the damage and its susceptibility to cracking. Its application to assessing mechanical damage in pipelines, including dent with gouge/crack, is presented. Examples are given to illustrate the effectiveness of the criterion for prediction of cracks in dents in pipelines.
Mechanical Damage Dent Critical strain Damage Model (DFDI) ASME B31.8
Ming Gao Ravi Krishnamurthy Samarth Tandon Udayasankar Arumugam
Blade Energy Partners,Houston,TX,USA
国际会议
北京
英文
1-10
2013-06-16（万方平台首次上网日期，不代表论文的发表时间）