In the construction of open channel drainage pipeline, the method of laying section by section after grooving and hoisting in case of well can be adopted; You can also use the method of reserving the well location, running the pipe first and hoisting the well bore at last. The pipe jacking construction should adopt the method of accurately measuring the well location, slotting and hoisting the well chamber first, and then jacking the pipe body into the reserved hole of the well chamber for construction. No matter which construction method is adopted, in order to achieve the effect of uniform stress on the foundation, a gravel cushion with a thickness of 5 ~ 10 cm must be laid under the floor of the precast concrete drainage inspection well in advance. The components of precast concrete drainage inspection well are designed as tongue and groove, and waterproof mortar is used to "sit slurry" when hoisting. Precast concrete drainage inspection wells are rigidly connected with pipelines through reserved holes, and waterproof mortar is filled around them. The differential settlement between the pipeline and the wellbore is solved by the deformation of the flexible interface between the first section and the second section.
Because of avoiding the use of clay brick masonry and wet concrete work on site, the work efficiency is obviously improved. The soil can be returned after fast water closing and pressure test, and it can be carried out during excavation, pipeline laying, well installation, soil return and road repair. The precast concrete drainage inspection well has good overall performance and good connection effect with the pipeline, which also improves the overall quality of the drainage pipeline.
As an alternative product of clay brick masonry manhole, precast concrete drainage manhole is suitable for building communities, general industrial and municipal drainage projects and areas with seismic fortification intensity of 8 degrees and below. It can be used for drainage pipeline engineering buried under urban roads where heavy vehicles (Automobile Super 20) pass. The maximum depth of the ground covering soil (from the ground to the inner surface of the manhole ground) is usually 6m, and the groundwater level is not higher than 0.5m below the ground.
The key technologies of assembled concrete inspection wells can be summarized as follows:
1. Determination of general well structure form and modulus series to meet the needs of new construction and renewal.
2. Convenient for transportation, hoisting and construction of well chamber, shaft section form and positioning skills of reserved holes.
3. Reliable and easy waterproof and sealing treatment shall be carried out between the well chamber, the shaft and the access pipe.