Abstract
The method of calculating the stable bed of a single section river seems to be almost established but there are many unsolved problems in case of double section rivers because the situation is very complicated.
Recently, with the exploitation of water resources, water intakes have been constructed or renovated in. a down stream river which has double sections. Therefore, there is an urgent necessity for a method of calculating the stable bed of the double section river.
This paper explains the calculation method of the following double section:
1. Unless the low water channel rises to the high water channel, deposition or scour occurs only in the low water channel, and the high water channel is fixed.
2. If the deposition of the low water channel progresses and the bed of the low water channel rises to the level of the high water channel, deposition takes place in the entire section including the high water channel.
3. The widths of both the high and low water channels are fixed.
The fundamental method of calculation is as follws: the equations which express the following:
1. Law of constant bed load-The bed load in a specific section must be constant.
2. Law of discharge-A specific section must discharge a given quantity.
3. Law of energy-A specified section must satisfy Bernoulli's theorem including head loss.47and the condition in which the flow profile becomes the double section are solved by simultaneous equations to obtain the unknown quantities-energy gradient, water depth and bed level of a specified section simultaneously.
It seems that the stable bed of the double section river including the part in which double section changes into single section, may be calculated consistently by this method.
