Investigation of the economic and sustainability aspects of cathodic protection method for corrosion prevention in marine structures

Abstract

Assessment of sustainability of structures requires calculation of life-cycle environmental and economic impacts. In this study, it is aimed to investigate economic value contribution of corrosion prevention, provided by galvanic cathodic protection method during the use life of marine structures, with consideration of sustainability. For a real wharf structure, cost of galvanic cathodic protection during the economic life of the structure and cost–benefit analysis of corrosion prevention are presented, and a method is proposed for understanding its economic contribution. Based on a real wharf structure’s design and corrosion protection calculations, and considering a use life of approximately 50 years, average loss of material due to corrosion is 0.16 mm/year, in absence of cathodic protection. Thus, for the wharf structure under investigation (two segments each 10 m × 45 m size supported by a total of 100 piles with diameter 100 cm and depth varying between 34–40 m), loss of material is estimated for each pile as 95 kg/year, totalling 475 tons for 100 piles in 50 years. This loss may lead to strengthening requirements for the structure. Comparing costs of strengthening with 91.1 tons of Al–Zn–In anode that would be spent for cathodic protection, economic gains can be estimated as 285,000 USD.