Riprap Stability and Navigation Tests for the Divide-Cut Section Tennessee-Tombigbee Waterway. Hydraulic Model Investigation

摘要

This investigation evaluated the stability of the in-place riprap on the Tennessee-Tombigbee Waterway and provided limited guidance for design of riprap on other navigable waterways. The in-place riprap was shown to be stable for all tows traveling at speed up to 80 to 90 percent of their theoretical limit speed. Only unloaded tows or service boats, which are capable of traveling near their limit speed, are capable of producing waves high enough to fail the riprap. Water-level drawdown and maximum wave height were measured for a wide range of tow speed and water depth. Greater water depths do not necessarily result in lower wave height or water-level drawdown. Tows simply go faster in the greater water depths, which prevents reduction of wave height or water-level drawdown. Two techniques relating riprap size to wave height were verified in this investigation. Several techniques relating ship speed to maximum wave height were evaluated with the measured data. (Author)