ANALYSIS OF FLOW RESISTANCE IN BRAIDED RIVER - A CASE STUDY

Abstract

The problem of predicting the resistance to flow in the rivers is complicated by the configuration of the bed changes in flow condition, bnd it becomes a very difficult task to describe the resistance due to these bed forms by a constant resistance coefficient. A basic knowledge of these factors would be useful for understanding resistance to flow in the alluvial river. However, a lot of ground is yet to be covered for arriving at a generalization of the variation of roughness in the alluvial rivers. The shape of the stream in plan is important in many design problems such as location of bridges. An alluvial channel stream seldom runs straight through a distance greater than about ten channel widths. Generally, it contains sinusoidal bends and it is often divided into several channels, which successively meet, and re-divide. Alluvial channels are categorized to possess straight, meandering, and braided pattern. Generally, braiding is favoured by high-energy fluvial environments with step valley gradient, large and. variable discharge, dominant bed load transport, and non-cohesive banks lacking stabilization by vegetation The present study has been focused on to conduct experiments by constructing a model of the Padma river in the brick masonry (flume) in the River Engineering laboratory of WRDTC and to ascertain a suitable reference (datum) level for the measurement of depth and surface width with the comparative assessment of different alternatives....