Characteristics of flow through multi-cell box culvert combined with broad crested weir

This study contains experimentally investigation of the hydraulic characteristics of flow over a broad crested weir and through multi-cell box culverts and both simultaneously, also to identifying the effect of parameters, such as upstream head, length, culvert inlet shape, culvert internal dimension, weir crest height, weir side slope angle, weir width, on the performance of combined structures .And so, it is aimed observe the discharge coefficient (Cd) variation of the combined structure. Finally, the equations are derived to the flow rate estimation through the combined structure. For this purpose twelve (12) glass material models of combined broad crested weir and multi-cell box culvert was manufactured and tested in a laboratory flume. These models were divided into four groups based on the box culvert dimensions; each group consisting of three models. The experiments were conducted in three stages, flow through the box culvert, flow over the broad crested weir, and flow through both the box culvert, and over the broad crested weir simultaneously. Dimensional analysis was performed to get the dimensionless parameters that the discharge coefficient depends on. Discharge coefficient prediction equations as a function of the dimensionless terms were developed using (a) multivariable linear regression and (b) multivariable power regression.