Municipal pipe network constructionThe construction of a municipal pipe network project is a complicated process that covers many aspects. The following is a detailed introduction:
##I. Pre-construction preparation
1. ** Engineering geological and geological survey **
- For areas with heavy rainfall, engineering geological and geological data are of utmost importance. The soil layer infiltration coefficient used must be reliable. If necessary, it needs to be determined by field pumping test.
- In complex soil layers, supplementary survey shall be conducted according to the requirements of rainfall, and the corresponding aquifer and impervious layer, the recharge relationship of underground water, the main aquifer and the substratum shall be identified.
2. ** Construction Equipment and Materials **
- Confirm the structure, length and quantity of the well point pipes, the model and quantity of the pumping machinery (including the spare capacity of the pump and the motor), and set up dual power sources if necessary.
- Prepare all kinds of pipeline materials required for construction, such as water supply pipeline, drainage pipeline, gas pipeline, heat pipeline, etc., and ensure that their quality meets the requirements of the project.
3. ** Construction drawings and plans **
- Draw the plan and profile layout and installation drawings of the well point drainage system, specify the sinking method of the well point pipe, the burial of the drainage ditch management and the selection of drainage location, etc.
- Formulate measures to prevent surface water and rainwater from entering the trench, as well as protective measures at the intersection of the well point pipeline and the construction road.
##2. Construction process
###(I) Earthwork
1. ** Trench and foundation pit excavation **
- The excavation must be carried out according to the calculation rules of the trench earth and stone. Where the width of the bottom of the trench shown in the diagram (excluding the widened working face) is less than 5m, and the length of the bottom of the trench is more than three times the width of the bottom, the trench project shall be implemented; where the area of the bottom of the trench shown in the diagram (excluding the widened working face) is less than 50m2, and the long side is less than three times the short side, the foundation pit project shall be implemented; in addition to the above provisions, the leveling project shall be implemented.
- The slope of trench and foundation pit shall be calculated according to the slope coefficient required by the design or construction organization design. If there is no regulation, it can be calculated according to the relevant standard table. During the calculation of the earth slope, the repetitive work volume at the junction shall not be deducted. The original trench foundation cushion layer shall be calculated from the upper surface of the cushion layer.
- The width of the foundation, pipeline and pipe network trench shall be calculated according to the design regulations. If there are no design regulations, the bottom width of the pipeline trench without foundation (cushion) shall be calculated according to the width of the working faces on the other two sides of the pipeline outer diameter; the bottom width of the pipeline trench with foundation (cushion) shall be calculated according to the width of the foundation (cushion) plus the width of the working faces on both sides; the bottom width of the trench supporting the retaining board shall be calculated according to the above regulations, and 0.1m shall be added to each side.
2. ** Earthwork Transportation and Backfilling **
- Backfilling volume of trenches and pits = excavation volume-volume of buried components; Backfilling volume of trenches = excavation volume-volume of pipes with a diameter of more than 500mm and volume of buried components.
- The volume of the backfilled soil and rock dregs shall be calculated in cubic meters according to the volume of the filled area after being compressed; the volume of the remaining transportation = the volume of excavation-the volume of the backfilled area.
###(II) Pipeling Project
1. ** Pipeling installation **
- Different types of pipes had different installation requirements. For example, the water supply pipeline had to ensure the supply of domestic water, production water, fire water, and municipal green and spraying water for the city, including the installation of water transmission pipeline and water distribution network.
- The installation of the drainage pipeline should realize the purpose of timely collection of urban domestic sewage, industrial waste water and rainwater, and transport the domestic sewage and industrial waste water to the sewage treatment plant for treatment and discharge, and discharge the rainwater nearby.
- The gas pipeline was responsible for distributing the gas from the gas distribution station to various users for their use; the thermal pipeline was used for heating, and there were hot water pipes and steam pipes; the power cable was used to transmit electricity to the city. It was classified according to its function and voltage, and the installation had to follow the corresponding specifications.
2. ** Production and installation of pipe fitting and steel support, and connection of new and old pipes **
- The installation of the pipe fitting must ensure that the connection is tight and meets the pressure and flow requirements of the piping system. The steel support must be strong and stable enough to support the weight of the pipeline and the stress during operation.
- When connecting the old and new pipes, pay attention to the connection process to ensure the safety and reliability of the overall operation of the connected pipeline system.
###(3) Anciliary facilities project
1. ** Construction of inspection wells and water wells **
- The construction of inspection wells and water wells must be carried out according to the design requirements, including their size, structure, materials, and so on. They play a role in inspecting, maintaining, and regulating the water flow in the pipe network system.
2. ** Gutter Project **
- The direction and slope of the drainage ditch project should be reasonably planned to ensure smooth drainage and prevent water accumulation from affecting the operation of the pipe network.
##3. Special Requirements During Construction
1. ** Well Point Rainfall Requirements **
- During transportation, loading, unloading, and stacking of the well point filter tubes, the filter screens shall be prevented from being damaged. Before running into the well point holes, the filter tubes must be checked one by one to ensure that the filter screens are in good condition.
- It is required to start the drainage 2 - 3 weeks before the excavation of the foundation pit, so that the soil has a certain degree of drainage and consolidation during excavation. After the start of the drainage, the water level of the water level observation pit buried inside and outside the foundation pit shall be regularly measured to ensure that the drainage depth meets the requirements. The depth of the water level drop of the underground water observation well outside the foundation pit shall not be greater than the environmental protection requirements.
- In order to reduce the impact of well point drainage on the surrounding environment, recharge well points, recharge sand wells and sand ditches can be set between the drainage pipe and the protected object.
2. ** Other considerations **
- During construction, take soil samples to check the range of the aquifer and the composition of soil particles. During the process of forming holes, check the straightness of the holes in time and measure the depth of the holes after they are formed.
- The well point pipe must be cleaned before it is put down. The position of the well pipe should be within the range of the stratum where water needs to be pumped, and the sand filter material should be filled around the well pipe. The sand filter material can also be placed on the specified length of the well pipe in advance before the well pipe is put down. When in use, the upper part of the well hole is sealed with a soil layer, and water is pumped immediately after the well pipe is buried to extract the powder and clay particles in the filter material, so as to ensure that the filter layer has good water penetration and the pumping effect of the well point.
- Before filling the sand, the mud in the hole should be diluted appropriately, the well pipe should be in the middle, and the filling height should not be less than 95% of the calculated value.
- The water quality of the pumping water is turbid, and the reason should be analyzed in time to prevent the ground from sinking due to the loss of mud and sand. The maintenance and inspection of the well point system should be strengthened to ensure that the well point can pump water normally and continuously. The pumping records should be made in detail.
##4. Post-construction Recovery
1. ** Road and sidewalk restored **
- After the completion of the pipe network construction, the road surface and sidewalk damaged during the construction process should be restored to the function and appearance before the construction.