Computer‐Aided Design for Channelization

Abstract

The bank protection and grade controls of a river channel must be designed to contain the design flood and extend below the potential riverbed scour. Because of the convoluted relationships governing the flow and sediment processes, mathematical simulation becomes an effective means of evaluating channelbed scour under any flow pattern and design configuration. Channelization of the Santa Cruz River has been designed based upon the pattern of river channel responses simulated using a calibrated mathematical model. Scour and fill of the channel bed invoked by the longitudinal imbalance in sediment load are simulated; they are also tied in with the effects of the streamwise variation in spiral motion that induces an uneven bed topography, characterized by greater scour near the concave bank. Variable top and toe elevations for hydraulic structures have been determined and employed to make more efficient use of construction materials while providing effective protection against erosion. The study demonstrates the procedure with which the design configuration of a flood control channel may be determined.