ABSTRACT
Channels with rigid linings such as concrete or shotcrete are considered highly durable and stable. The design criteria for a concrete channel are essentially developed to control the water flow velocity for safety. A concrete channel shall be equipped with a subdrain system that has adequate weeping holes to release the static pressure built up in the saturated soil layers behind and/or beneath the concrete panels. The stability of a supercritical flow is sensitive to channel shape, lining roughness, curvature of alignment, and invert slope. Development of roll waves is a continuous amplification of a small perturbation. Cross waves at a bend can be analyzed using the unit-width approach under the following assumptions: the channel is horizontal or the weight of water body is ignored, and the friction loss in the flow is negligible. Oblique jump is similar to the shock wave in a high-speed air flow.
