Comparison of Retrofits for Three Strut-Arm Tainter Gates Using a Longevity Corrosion Maintenance Factor

Abstract

This paper presents a methodology to compare various Tainter gate strut-arm retrofit techniques based on the longevity corrosion maintenance (LCM) factor. The rating system is designed to encourage agencies to select retrofits that will better upgrade existing conditions to meet current design standards for hydraulic steel structures and achieve a long design life. An overview of past Tainter gate failures, governing strut-arm load cases, past strut-arm retrofit strategies, current design standards for hydraulic steel structures, and the consequences of welding or bolting to existing structures has been considered in this study as evidence to support the proposed Tainter gate retrofit comparison methodology. An example problem illustrates how to determine the LCM factor and assign a LCM grade for three retrofit scenarios.