Design and Calibration of a Compound Sharp-Crested Weir

This paper describes the design and calibration of a compound sharp-crested weir consisting of two triangular parts with different notch angles. This weir provides accurate measurement for a wide range of flows without discontinuities. The lower triangular part of the weir handles the normal range of discharges at the measurement structure while the upper part measures the occasional higher peak flows. This weir will be installed on the crest of small concrete gravity dams for measuring runoff in experimental catchments. The weir was calibrated in the laboratory using a scaled model. Different geometries (combination of notch angles) were tested in order to validate the proposed theoretical discharge equations.