Author(s): Gustavo Carrasco; Jorge Reyes-Salazar

Linked Author(s): Jorge Reyes, Gustavo Carrasco

Keywords: Scour; Spillways; Physical model

Abstract: Most of the studies are carried out experimentally and are aimed at developing empirical equations that estimate the maximum depth of erosion, in an increasingly precise way, because the physical processes involved in erosion processes are relatively complex. The present work studies in hydraulic model the erosion process in a terminal structure with ski-jump used as a mechanism of energy dissipation of the excess flow in a dam. Some of this energy is dissipated in the air due to friction and some is dissipated at the point of impact of the jet with the bed downstream, generating the excavation of a large erosion hole. The physical modeling, carried out at the facilities of the Institute of Hydraulics, Hydrology and Sanitary Engineering (IHHS) of the University of Piura, comprised a group of tests organized into three series: (1) model calibration tests, (2) fixed bed tests and (3) moving bed tests downstream of the dam. The objectives of this work are, first, to evaluate the efficiency of the most used equations to estimate the maximum erosion in non-cohesive bed due to the impact of a jet at the exit of a landfill with ski jump. Secondly, the objective was to obtain a more precise expression for this estimate. Based on the analysis of erosion data recorded in the model, it was concluded that the empirical equation proposed by Chain, in 1973, is the most accurate to determine the maximum erosion of the project. Also, using consistent dimensional analysis and linear regression techniques, a new equation, the IHhs was proposed to estimate the maximum erosion depth, even improving the estimation of the Chain equation.

DOI: https://doi.org/10.3850/978-90-833476-1-5_iahr40wc-p0950-cd

Year: 2023