Optimization Design of Long-Span Steel Bridge Deck Pavement System

Abstract

Asphalt mixtures have been widely used for wearing surfaces on steel decks of long-span bridges. Due to the unique mechanical and environmental conditions of steel decks, requirements for paving materials and paving patterns are different from those for regular road pavements. Currently there are no commonly adopted design theories or procedures for steel bridge deck surfacing. Premature failures of deck pavements have often been observed on steel bridges, particularly on the newly-built long-span bridges in China. Therefore, two main objectives are identified in this paper as: 1) integrating the separate design processes for the bridge structure and the deck pavement into one interactive process; 2), establishing the methodology of determining pavement system parameters. Systematic research has been conducted to develop the design theory and procedure, from many aspects including pavement materials and structure, mechanistic characteristics of the wearing surfaces on steel decks, fatigue properties, axle-load equivalency conversion, and optimization design procedure. The empirical-mechanistic approach is employed for the optimization of design. The case study shows that it is more feasible to consider the orthotropic deck and its pavement as a whole structural system during bridge design.