ASSESSMENT AND RETROFITTING OF MASONRY ARCH BRIDGES

Abstract

The Masonry arch bridges were built were built on a very large scale in India during 19th century and first quarter of 20th century. However, the design and construction details for most of these bridges is not known. Still some of these bridges have withstood the increased axle load and the increased traffic volume and speed. Many of them are showing the signs of distress due to various reasons. The demolition and replacement of all such bridges in one go would be impracticable as well as uneconomical. Various methods used for the determination of strength of the masonry arch bridges have been studied along with modes of failure. Step-by-Step method has been used for the analysis of masonry arch model, which was experimentally tested for load carrying capacity in the laboratory. The sequence of the formation of hinges has been studied in detail. Different methods of restoration and retrofitting of masonry arch bridges have been covered in brief and some of them are used to strengthen the tested arches. Finally the comparison of the load carrying capacity of strengthened and original test arches has been carried out to study the efficacy of the employed retrofitting techniques.