Leachate Pipe, Collection Ditch, Inspection Well Engineering Construction Method
1. The leachate pipes of this project are HDPE φ250 and φ350 plastic pipes, which are all ordered from professional manufacturers.
2. The construction sequence is: acceptance inspection of the impervious membrane protective layer → cleaning the construction surface → installation → inspection → acceptance.
3. The construction process is as follows: the primary and secondary leachate pipes of the landfill are laid out according to the plan position, and the protective layer of the soil in the plane position of the pipe is cleaned according to the laid outline. The impermeable membrane must not be damaged. The protective layer with gravel and coarse sand must be evenly laid, compacted and compacted, and its thickness and slope meet the design requirements. The backfill soil at the trench must be layered and compacted, and the backfill compaction is more than 90%.
4. Main construction quality measures
(1) Pipeline laying shall be carried out after positioning according to the position of the landfill pit, the centerline of the ring road, the planned pile position and coordinate values.
(2) The elevation of the bottom of the landfill pit must be re-tested before construction, and check whether the impervious layer and the padding above the impervious layer meet the requirements.
(3) The construction operation of the PE leachate pipe network must meet the design requirements. The preceding project must be inspected and accepted before construction. The pipe network can be installed and constructed, and quality acceptance should be performed according to the project sequence during the construction process.
(4) The materials used must meet the design requirements and have quality certification documents. HDPE pipes must be manufactured using the same raw materials and formula as HDPE barrier membranes. They must be inspected before use. Certificates must not be used.
(5) The foundation must meet the design requirements. Before the construction of the anti-seepage element of the transmembrane pipe, it must be tested for water by supervision, inspection, and observation for 24 hours without leakage, and construction can be performed after signing.
(6) The installation should be carried out under the rain-free weather between 5 and 40 ° C. The installation and construction of the HDPE pipeline network are determined according to the design requirements of the drawings. After the foundation of the pipeline is completed, the installation sequence of the pipeline network is started from low to high. After all the installation is completed, the inspection is qualified. The network is implemented on the basis of the pipe, re-inspected, and the next process can be carried out only after meeting the design requirements.
(7) The pipe is cut off, the nozzle is perpendicular to the axis, and the length of the pipe is 10mm longer than the designed length.
(8) After the installation of the PE pipe, the design requirements must be met. The deviation of the alignment of the nozzle must not be greater than 15% of the thickness of the pipe wall. Otherwise, it must be disconnected and re-welded.
(9) The braking force at the place is not less than 70% of the pipe breaking force. Weld strength is only tested in the test room before installation. Welded welds must not be subjected to destructive tests.
(10) Personnel entering the site shall not step over the welded pipes, and shall not damage the pipeline when entering the next process after installation. If there is any damage, repair it in time.