“DISEÑO HIDRÁULICO DE VERTEDORES ESCALONADOS

Abstract

In recent decades, México entered into the development of stepped spillways and hydraulics works to reduce the cost and the construction time. These stepped spillways can be present for different types of water discharge; a skimming flow (FRAS), a nappe flow (FEXE) and of the zone of transition flow (FTRANS) between the last two. The three flows produce in different ways a mixing of the air in the mass of water by the turbulence that is generated by them, the FEXE in general introduces air directly by the crash of the flow against the steps, while the FRAS introduces the air by the strong turbulence that is generated in to the potential of the flow energy transformed in to the kinetic energy to while this crosses the pseudo bottom generated by the corners of the steps. The geometry of the steps and the flow discharge that presents it self in the spillways, determines the behavior of the flow, however, the geometry that the spillways could present has always been determined by the construction method of the Roller compacted concrete (RCC), establishing steps that are multiples of 30 cm all along spillways. In the development of research are studied the behavioral theories, design and analysis of stepped spillways, establishing the importance of the geometry of the steps, taking into account the shape and type of flow that is desired in the chute to develop the project from the viewpoint of the design flow discharge. In the study of the type of flows over the spillways, it is important to locate the point where the mixing of the air-water known as inception begins (PI), which has been set in different forms by different researchers. The importance of the locating the inception point of the air that the flow consist that the water under on the fact that than this point is reduced of the notable way the effects provoke the cavitations risks, thanks to the entering in a of the air in atmospheric pressure which leaves, standing in uncovered the zone water above to the apparition of the white water (aerated flow). So it is established one equation to determinate the PI using the obtained data by diverse researchers in his probes, just as they obtained by hydraulic models made in the lab of hydraulics of the Escuela Superior de Ingeniería y Arquitectura, U. P. Zacatenco This thesis defined the methodology of the geometry of the stepped spillways, from the hydraulic configuration of the behavior of the flow in the steps, by presenting examples of application to the design and review of the stepped spillways and thus establishes the limits and the reach of the proposed methodology.