Abstract
The shell plate of oil storage tank is an important evaluating component in the Fitness-For Service Assessment, because it is required to have a sufficient strength against to the static and dynamic pressure in case of operation and an earthquake. This paper reported the analysis results of elastic-plastic strain occurred at the local thin areas (LTAs) of shell plate obtained by using a nonlinear isotropic/kinematic hardening model. The strain tendency has been investigated when LTA is assumed as a rectangular area or a ring area and its size as study parameters. The investigation results show that there is a tendency for elasto-plastic strain to be going up when the longitudinal length of LTA lengthens gradually and the thickness of side plate is decreased. But there is not any ratcheting behavior in LTA because of small strain range although subjected to cyclic loading.
