Structural integrity assessment of storage tanks based on damaged surface reconstruction and finite element modelling

Resumo

This research paper aims to discuss an analysis methodology developed for structural integrity
assessment of storage tanks. Such methodology is based on the assessment of the damaged structure, considering
the pre-deformed geometry, via stresses analysis. Then, a finite element model is generated, based on the
deformed surface of the structural system, through laser scanning technology. This way, it is possible to detect
the real geometry that explicitly includes the damages present on the studied storage tank. This way in this work,
a real case study is investigated having in mind an Atmospheric Storage Tank (AST) located in an industrial
floor related to the oil and gas industry. The equipment object of this analysis presents a cylindrical geometry
with approximately 45 m diameter and a 14.63 m height and is utilized for diesel oil storage. The storage tank

presents deformations on its shell (cylindrical surface of the structure), and in order to evaluate its Fitness-For-
Service (FFS), i.e. evaluate whether the equipment is suitable to continue in operation, with existing damages, a

laser scanning was performed on the storage tank shell. In sequence, the stresses analysis methodology provided
by API (American Petroleum Institute) design codes was adopted to the assessment of the structural response.
The results obtained along this research work show that the developed analysis methodology used for the
evaluation of the damaged storage tank is very effective and also can reduce maintenance costs as well as losses
due to the time that the structure needs to be out-of-operation.