Repairs to major European highway bridge

摘要

The current 45m-wide, dual three-lane bridge, opened in the late-1970s and built on the original concrete piers of the previous structure, is believed to be one of the most heavily trafficked bridges in Europe, carrying around 120,000 vehicles a day. During routine inspections of the nation's steel bridges, fatigue cracking was found in Moerdijk's thin steel deck plate, threatening the structure's integrity and leading the Dutch Ministry of Transport to carry out extensive repairs and strengthening involving Doornbos and Conjet hydro-demolition equipment.rnThe restoration, costing some €10.5 million and designed by the Dutch Ministry of Transport, involves repairing the cracks followed by what is believed to be one of the first major applications of a special thin, very high-strength concrete overlay wearing course of 105MPa. The 50-70mm-thick, high-performance steel fabric reinforced concrete overlay is based on a secret blended recipe and is additionally reinforced with steel and polyethylene fibres. It aims to spread the traffic loading and stiffen the 12mm-thick steel deck plate, eliminating future fatigue problems and extending the life of the bridge.