Hydraulic Design Of Energy Dissipators For Culverts And Channels

Under many circumstances, discharges from culverts and channels may cause erosion problems. To mitigate this erosion, discharge energy can be dissipated prior to release downstream. The purpose of this circular is to provide design procedures for energy dissipator designs for highway applications. The first six chapters of this circular provide general information that is used to support the remaining design chapters. Chapter 1 (this chapter) discusses the overall analysis framework that is recommended and provides a matrix of available dissipators and their constraints. Chapter 2 provides an overview of erosion hazards that exist at both inlets and outlets. Chapter 3 provides a more precise approach for analyzing outlet velocity than is found in HDS 5. Chapter 4 provides procedures for calculating the depth and velocity through transitions. Chapter 5 provides design procedures for calculating the size of scour holes at culvert outlets. Chapter 6 provides an overview of hydraulic jumps...

The purpose of this publication is to provide design information for analyzing and mitigating energy dissipation problems at culvert outlets and in open channels. It provides general information on the overall design process, erosion hazards, and culvert outlet velocity and velocity modification. These provide a background and framework for anticipating dissipation problems. In addition to describing the overall design process, design examples to compare selected energy dissipators are provided. Also provided are assessment tools for considering flow transitions, scour, and hydraulic jumps.