Experimental Study of the Hydraulic Performance of Continuous Transverse Grates

Abstract

Better understanding of the hydraulic performance of stormwater inlets which serve as the linkage between the surface drainage system and the underground sewer system is important to avoid urban flooding. Continuous transverse grates were not well studied in the literature, and, therefore, eight types of such grates commonly used in China were examined experimentally in this study. A full-scale physical model simulating a 12-m-long and 3-m-wide road was constructed for 320 hydraulic tests with different approaching flow rates and road longitudinal slopes. Hydraulic efficiencies of the grates under different conditions were calculated, and their influencing factors were analyzed, including the Froude number and the grate’s geometry (grate length, effective length, effective width, effective length ratio, effective width ratio, opening style, and opening rate). Empirical equations are presented to relate the hydraulic efficiency and influencing factors. This research is useful for understanding continuous transverse grates and improving the engineering design of the grates.