Reliability of maintained, corrosion protected plates subjected to non-linear corrosion and compressive loads

A model is proposed for the non-linear general corrosion wastage in a plate, which is able to describe an initial period without corrosion due to the presence of a corrosion protection system, and an exponential increase in wastage up to a steady-state value. The influence of adopting this model instead of a linear one is demonstrated by studying the reliability of a corrosion-protected plate subjected to compressive loads, and maintenance actions. The paper examines how the plate collapse strength will vary in time as a result of generalised corrosion and plate repair. In the presence of general corrosion, the plate thickness will decrease at a random rate as a function of time and will affect the net plate section resisting the applied load. The collapse strength against compressive loading is described by a function of time and the resulting reliability is quantified. The sensitivity of the reliability estimates with respect to several parameters is also studied. The reliability is predicted by a time-variant formulation and the effects of repair actions in the reliability assessment are shown.

[1]  Jeom Kee Paik,et al.  Probabilistic corrosion rate estimation model for longitudinal strength members of bulk carriers , 1998 .

[2]  R. G. Bea,et al.  Towards optimal inspection strategies for fatigue and corrosion damage. Discussion. Authors' closure , 1997 .

[3]  D. Faulkner.  A REVIEW OF EFFECTIVE PLATING TO BE USED IN THE ANALYSIS OF STIFFENED PLATING IN BENDING AND COMPRESSION , 1973 .

[4]  C. Guedes Soares,et al.  Reliability of maintained ship hulls subjected to corrosion and fatigue under combined loading , 1996 .

[5]  C. Soares,et al.  PROBABILISTIC MODELLING OF THE EFFECT OF INITIAL IMPERFECTIONS ON THE COMPRESSIVE STRENGTH OF RECTANGULAR PLATES , 1987 .

[6]  José Manuel Gordo,et al.  Collapse strength of rectangular plates under transverse compression , 1996 .

[7]  O. Ditlevsen.  Generalized Second Moment Reliability Index , 1979 .

[8]  C. Guedes Soares,et al.  Simulation of the ultimate compressive strength of unstiffened rectangular plates , 1993 .

[9]  C. Guedes Soares,et al.  Design equation for the compressive strength of unstiffened plate elements with initial imperfections , 1988 .

[10]  C. Guedes Soares,et al.  Uncertainty modelling in plate buckling , 1988 .

[11]  B. Ayyub,et al.  DETERMINING THE EFFECTS OF CORROSION ON STEEL STRUCTURES: A PROBABILISTIC APPROACH , 1992 .

[12]  Shi,et al.  IN-SERVICE ASSESSMENT OF SHIP STRUCTURES: EFFECTS OF GENERAL CORROSION ON ULTIMATE STRENGTH , 1993 .

[13]  A. Naess.  Technical Note: On a rational approach to extreme value analysis , 1984 .

[14]  C. Soares.  Probabilistic Modelling of the Strength of Flat Compression Members , 1997 .

[15]  C. Guedes Soares,et al.  Compressive strength of rectangular plates under biaxial load and lateral pressure , 1996 .

[16]  Ronald Z. Hodgman,et al.  Microbial influenced corrosion in cargo oil tanks of crude oil tankers , 1997 .

[17]  C. Guedes Soares.  Probabilistic methods for structural design , 1997 .

[18]  Toshiro Arima,et al.  A Study on Developing a Rational Corrosion Protection System of Hull Structures(Technical Reports on Inspection & Preventive Maintenance of Hull Structures) , 1994 .

[19]  Masanobu Shinozuka,et al.  Structural Safety and Reliability , 2000 .

[20]  I. Orisamolu,et al.  Probabilistic assessment of corrosion effects on the damage tolerance of aircraft structures , 1997 .

[21]  M. Schumacher,et al.  Seawater corrosion handbook , 1979 .