Evaluation Method for Crack Propagation Behaviors at Shell-Annular Joint in Petroleum Storage Tank under Repeated Large Deformation (Paper 1)/Crack Propagation Behaviors in Tension-Compression Test

摘要

Many countries have suffered from large earthquakes in the past few decades. Especially in Petroleum Storage Tank, extensive efforts are required to estimate the fracture behavior under cyclic plastic strains so as to prevent or minimize fatal accidents. Crack growth rates under cyclic loads have been generally analyzed by Paris'law by using a linear elastic fracture mechanics concept, "#DELTA#K" stress intensity factor range. But, this approach cannot be valid in the repeated large plastic deformations.This paper proposes an approximate method to evaluate crack growth rates under repeated large plastic deformation by using an easier formulation based on an approximate analysis of pseudo J parameter. Crack growth experiments have been conducted under cyclic axial plastic loadings in order to verify the validity of the proposed formula.