Experimental study on interceptor performance of bridge rainwater inlet

ABSTRACT Rainwater inlets are important for bridge drainage, and this paper carries out modeling tests on the interception performance of bridge rainwater inlets in the Daxinganling region of China. The effects of slope, different inlet methods, and grate opening forms on the interception efficiency of rainwater inlets are mainly investigated. The results show: (1) Rainwater inlet interception efficiency increases with increasing cross slope and decreases with increasing longitudinal slope. (2) The innovatively proposed inlet method of spraying above the flume, which is less efficient than the rainwater inlet interception of the diffuse flow method at the front of the flume, the inlet method is more in line with the actual situation. (3) Combined with the weir flow formula to fit the interception efficiency formula, the relative error between the predicted and measured values of the interception efficiency of the formula is less than 5%, indicating the applicability of the formula. (4) Comparing the interception efficiency of grates with different opening forms, it is concluded that the longitudinal curved opening is the best, followed by the longitudinal linear opening, and the transverse opening is the worst. In the transverse opening grates, the fewer longitudinal bars, the better the interception efficiency.