Measures for Preventing and Extinguishing Dangerous Water Flow Patterns in the Downstream Section of Road Culverts

Road culverts are the most common type of artificial structure on highways. It is important to note that the downstream section of these structures operates under challenging conditions characterized by a significant uneven distribution of specific discharges, high kinetic energy of the flow, and a stream saturated with bottom sediments, stones, and debris. These factors cause erosion of the downstream section and destruction of both the embankment and the culvert itself.Preventing the formation of dangerous water flow patterns in the downstream section of road culverts can be achieved through the use of engineering structures that alter the flow mechanism and velocity structure behind the culvert. This can be accomplished by installing energy dissipators, which help to equalize the flow distribution across the width of the downstream channel, normalize flow depths and velocities, and reduce their pulsations.One of the weakest areas of road culverts is the downstream zone, which is often subject to deformation. This occurs when water exits a circular culvert into a trapezoidal channel, flow disruption, vortex zones, and high bottom velocities form. Therefore, it is necessary to make the water flow spread without disruption, with a more favorable velocity structure and reduced actual velocities near the bottom.Currently, there is widespread damage to downstream sections, which necessitates the development of new downstream structural designs for road drainage systems. Two main approaches can be distinguished for addressing the problem of reinforcing culvert downstream sections: complete abandonment of energy dissipator structures with relocation of the scour hole far from the road embankment; or the use of various types of energy dissipators, deflectors, or diffusers.To prevent damage to road culverts by water flow in the downstream section, it is essential to eliminate dangerous water flow patterns.This article discusses measures for preventing and damping dangerous water flow patterns in the downstream section of road culverts.