DESIGN ANALYSIS OF RIVER TRAINING WORKS FOR GRAVEL BED RIVER - A CASE STUDY

Abstract

The gravel bed rivers differ from those of sand bed rivers in many aspects such as resistance to flow, sediment movement, unpredictable geological features that may be encountered under river bed and sides, variedly changing flow, etc and thus river flow possesses complex mechanism. Hence, prediction of river behaviour in such river is very difficult. An attempt has been made here to analyse the design aspect of river training works in gravel bed rivers with the present day state of art. The gravel bed rivers are generally found in mountainous regions. They are• encountered with flashy floods with tremendous velocity which carries heavy bed load containing gravels, cobbles and boulders. The problems in the gravel bed rivers are generally associated with bank erosion and sometimes, overtopping of banks. The failures of existing structures are found mainly due to insufficient flow area to pass the high flood discharge and outflanking of structures. This dissertation includes the study of river behaviours, the problems that may arise thereof and design analyses and procedures to obtain most suitable and practicable solution. An approach with , thorough investigation in this respect has been adopted....