Gomposite Geomembrane Impervious Construction Process
Process principle: The composite geomembrane is a geosynthetic material with a good anti-seepage effect. The composite geomembrane is laid on the slope surface that needs anti-seepage treatment, and the sand cushion layer and concrete are laid on it. Form a whole completely closed impervious system.
Process flow: Before the laying of the composite geomembrane, the earthwork filling of the channel and the trimming of the slope are completed, the flatness and compactness of the slope have reached the design requirements and the composite geomembrane can be laid after the acceptance by the supervision engineer.
1. Quality inspection of composite geomembrane materials. The composite geomembrane used in this project is two cloth and one membrane composite geomembrane. The product is produced by Shandong Taifeng Plastic Geotechnical Co., Ltd. Before use, it was entrusted to the Heilongjiang Province Hydraulic Engineering Quality Inspection Center Station to inspect the product. Each technical indicator is tested, and all indicators meet the standard requirements and design requirements.
2. The dike slope is cleaned and the site is leveled, all sharp-pointed debris is removed, backfill ramming of the under the slope, and rich slope cutting and leveling are qualified after supervision and acceptance to provide a working surface for the laying of the composite geomembrane.
3. For geomembrane splicing in the field, in order to facilitate the construction and ensure the quality of splicing, the composite geomembrane should be as wide as possible to reduce the amount of on-site splicing. Before construction, it should be cut in the unit according to the width and field length of the composite geomembrane. Spliced into a block of the required size, rolled on a steel pipe, manually transferred to the work surface and laid.
Laying method of composite geomembrane: The laying of composite geomembrane is divided into two parts: the bottom of the canal and the slope. Laying method: roll horizontally along the axis of the channel. After the slope is paved and accepted, it is rolled along the axis of the slope, and the composite geomembrane at the bottom of the canal is connected in a T-shape.
Technical requirements for laying of composite geomembrane: laying should be carried out in dry and warm weather. In order to facilitate splicing and prevent stress concentration, the laying of composite geomembrane uses a wave-shaped relaxation method with a margin of about 1.5%. On, it is required that the composite geomembrane and the slope should be flat and have no protruding folds. Construction personnel should wear flat shoes or soft rubber shoes, and it is strictly forbidden to wear spiked shoes to avoid stepping on the geomembrane. If the geomembrane is found to be damaged during construction, it should be repaired in time.
Splicing of composite geomembrane
1. This project uses two cloths and one membrane composite geomembrane. Welding is performed by hot-melt welding. The splicing includes geotextile seam and geomembrane welding. In order to ensure the quality of welding, welding should be performed in the factory as much as possible, but for construction Convenient, the width of the composite geomembrane should not be too wide, and it must be spliced at the construction site.
2. The quality of the composite geomembrane welding is the key to the success or failure of the anti-seepage performance of the composite geomembrane. Therefore, it is important to do the welding of the geomembrane to ensure the welding quality. Therefore, the manufacturer should send professional technicians to the site to operate the geomembrane welding. , Guidance, training, using special welding equipment for geomembrane. The geomembrane welding of this project uses a zpr-210v heat-sealing geomembrane welding machine, and the geotextile is sewn by a portable sealing machine.
3. The welding process of two cloth and one membrane composite geomembrane for this project:
4. Welding process: After the first geomembrane is laid, the edges to be welded are folded (about 60cm wide), and the second one is laid on the first film in the opposite direction, and the welding edge of the two films is adjusted to make it Lap 10cm.
5. Before welding, use a hairdryer to blow off sand, dirt and other dirt on the film surface to ensure that the film surface is clean. Place a long wooden board under the welding part so that the welding machine can walk on a flat base surface to ensure welding quality Before the actual welding, test welding is performed according to the construction temperature to determine the walking speed and welding temperature. Generally, the walking speed is 1.5 to 2.5 m / s, and the welding temperature is 220 to 300 ° C. There are two splicing welds, each 10mm wide, and a 10mm cavity is left between the two welds. Use this cavity to check the quality of the weld.