Outlet Works for Cerrillos Dam, Cerrillos River,and Portugues Dam, Portugues River,Puerto Rico;Hydraulic Model Investigation.

摘要

Tests were conducted on a 1:24-scale model of the outlet works for the Cerrillos and Portugues Dams located in Puerto Rico. The purpose of the model investigation was to determine the performance of the stilling basins for the full range of discharges with minimum head pool and the optimum riprap protection plan for the exit channel. The model reproduced a schematic of the intake tower, conduit transition, 60 percent of the conduit length, the stilling basins, and exit channel. The original design stilling basin (type 1) for the Cerrillos outlet works performed satisfactorily for low discharges of 500 cfs and less, and for the higher range of discharges between 1500 and 2500 cfs (design discharge). The conduits of both Cerrillos and Portugues outlet works were designed to provide for river diversion during construction of the dams. When the dams are completed, the flow will be regulated so that only bank-full capacities will be passed through the stilling basins. The conduit capacities were 4500 cfs for Cerrillos and 5300 cfs for Portugues. However, the stilling basins were designed for 2500 cfs (Cerrillos) and 1100 cfs (Portugues), the bank-full capacities downstream. Therefore, considerable damage to the downstream exit channel will occur should it become necessary to pass the conduit design flow through the outlet works.