Channel Widths in Bends and Straight Reaches between Bends for Push Towing. Hydraulic Model Investigation.

This investigation was concerned with the development of parameters that could be used as a guide in the layout and design of shallow-draft waterways, particularly bends and straight reaches between bends. Results are based largely on model studies using different linear scales and some limited prototype tests. In negotiating a bend or making a turn, tows occupy a greater channel width than in straight reaches. The width of channel required depends on the deflection or drift angle which varies with the size of two, radius of the bend or tunr, length of the bend up to about 90 deg, alignment and velocity of currents, weather conditions, direction of travel upstream or downstream draft of two with respect to channel depth, alignment and location of the tow when entering the bend, and maneuverability of the tow. If the deflection angle assumed by a tow in negotiating a bend is known, the width of channel required can be computed using one of the equations from this study. Results include curves showing the deflection angle assumed by tows of various sizes in bends of different curvatures with and without currents. Also covered are bends consisting of compound curves, bends with irregular bank lines, and lengths of straight reaches required between alternate bends.