How to choose the rain outlet?

There are four types of gullies: plane calculation formula, offset ditch formula, combined formula and vertical calculation formula, which are divided into single grate, double grate and multi grate according to the algorithm. The rain nozzle manipulator is divided into three materials: ductile iron, gray cast iron and steel grating.

Single grate is a kind of open hearth grate. This kind of drainage ditch is as high as the flat stone of the road and basically the same width. Rainwater is collected through the cross slope of the road. The other is the lateral drainage type (it should be the partial ditch type), and this drainage is through the side stone.

Usually, the single grate rainwater outlet is located on the road, while the double grate rainwater outlet is located on the ground of the square. Displacement of flat grate single grate rainwater outlet: 0L/s, and displacement of flat grate double grate rainwater outlet: 35l/s.

Discharge capacity of multi-grated rainwater outlets: It is considered according to whether rainwater outlets are set in the plot. If arranged, only the rainwater on the road surface needs to be considered; If it is not laid, the rainwater in the plot should be considered. In addition, when the road slope is small or the road is important, double or even more rain outlets should be set.

Extended data:

1. Rainwater outlets should be set at road catchment points, upstream of crosswalks, upstream of entrances and exits of units along the street, and at the exits of neighborhoods or courtyards near surface runoff. Rainwater outlets should be appropriately increased in low-lying and waterlogged sections of roads as needed.

2. The types of rain outlets are flat calculation type, vertical type and combined type. Horizontal calculation formula: the rain mouth has a stone screen formula and the ground level formula. The Shi Ping formula is suitable for roads with rocks. The ground leveling formula is suitable for the pavement without stones and low-lying water accumulation. The vertical rainwater outlet has vertical pass and vertical calculation formula, which is suitable for roads with rocks. Among them, the vertical hole type is suitable for the place where the calculation gap is easily blocked by debris.

Combined rainwater outlet is a comprehensive form of horizontal and vertical calculation, which is suitable for places with wide road surface, concentrated rock and runoff and many sundries.

3. The drainage capacity of ordinary storm sewer is about 20 1/s, and that of combined storm sewer is about 30/s.. The discharge capacity of the rain outlet which is easily blocked by sundries in heavy rain should be multiplied by the coefficient of 0.5~0.7. The discharge capacity of multi-calculation rainwater outlet and vertical rainwater outlet is determined by calculation.

Baidu encyclopedia-Dan Qing Yu kou