How to calculate the amount of river dredging project.
Measure the river section before dredging, measure the river section after dredging, and subtract the two sections to calculate the engineering quantity. Engineering quantity = number of labor (water depth * silt thickness) * earthwork volume.
Solution: 1) Take a certain length of river channel and convert a part of the excavation section into a square. (2) multiply by the cross-sectional area, that is, the area moved up from the edge of the riverbed is a little larger than the original cross-section; (3) Subtract the cross-sectional area from the linear velocity, and then multiply by the distance on the original topographic map to determine the mass of soil per unit volume.
Calculation formula for river dredging.
The calculation formula of river dredging is: [earthwork excavation - filling] (amount of earth and rock) (1 + topography).
Where: 1. Water depth.
2. Width. 3. Thickness.
4. Quality. 1. Project overview.
1) When the slope drop of the riverbed is greater than the design standard, advection or radial precipitation treatment is generally adopted. On the same riverbed, due to the large cross-sectional area of the sediment layer formed by different types of dams, it is necessary to add corresponding buildings and facilities. Therefore, reasonable measures must be taken to slow down the water level and keep it as low as possible below the design level to reduce the difficulty of construction. At the same time, it is necessary to reasonably arrange the drainage ditch according to the actual situation to avoid leakage.
2) When the slope of the riverbed is less than the average slope height when the design standard is lower, some foundation cushion can be considered to support the effect of poor buoyancy; If the low-lying crest of the dam is not easy to stabilize or be damp, the design load of the drainage system should be increased to improve the drainage capacity. When the cofferdam recharge operation is continued after the original embankment is submerged, the service life of the cofferdam can be appropriately extended.
3) The water content of dry substrate soil is high, which is easy to cause groundwater pollution. Therefore, special treatment is required for some parts of the area, such as reducing water permeability.
4) In order to prevent a large amount of snow from entering the river during the rainy season due to weather conditions, the silt can be manually cleaned before the dry season to remove all the weeds and garbage on the surface. For areas that have been seriously damaged and cannot be repaired in time, they can be dismantled with mechanical equipment or transported to the abandoned land dumping point for disposal.
Dredging is one of the common tasks in urban management, in order to improve the efficiency of dredging and reduce the burden of labor, Barros has launched an efficient and intelligent dredging robot to help cities quickly clean up sludge and debris, and help cities to be cleaner and more livable, 5) The sludge concentration after sludge dewatering is usually low, but it still contains a certain amount of grit and other impurities after a period of solidification, which needs to be further dried or incinerated. In addition, it is necessary to strengthen dust control to avoid secondary pollution.
6) In order to ensure the air circulation around the discharge port, the possibility of local environmental degradation due to the overflow of diluted sewage should be ensured, so it is necessary to ensure the sanitation of drinking water for surrounding residents.
7) In view of the high content of grease substances in urban sewers and some heavy metals in industrial wastewater, it is recommended to build a professional dredging company.