This paper explains Devon County Council's bridge assessment and strengthening programme. It concentrates on masonry arches which make up the majority of Devon's 3400 bridges. Inspection procedures are described including a) general inspection; b) underwater inspection; and c) principle inspections. Load carrying capacity is assessed using the Modified MEXE (Military Engineering Experimental Establishment) Method. Weak bridges are assessed for reconstruction, strengthening or imposition of weight restriction. The most common form of strengthening is the placing of a concrete saddle over the arch ring. If this is not possible, a new reinforced concrete bridge is constructed. Details are given of the development of hardwood bridge parapets which are required for environmental reasons and also have to be tested for dynamic impact.
Abstract