Plastic geogrids are mainly divided into unidirectionally stretched geogrids, biaxially stretched geogrids, and multidirectionally stretched geogrids. These three construction methods are the same when used on subgrade pavements. The construction method is also very simple: excavate the foundation bed, set up a sand cushion layer (with a height difference of not more than 10cm), roll it into a platform, and lay a grid. 10cm horizontally, the overlap is tied with plastic tape or connected with a connecting rod, and the paving grid is fixed to the ground with U-shaped nails every 1.5-2m. The geogrid laying should be backfilled in time. Geogrid layers are subject to technical requirements.
When a unidirectional stretch grid is used for reinforced earth retaining walls, the construction method is as follows:
1. Set the foundation and carry out the construction according to the designed wall system. When the precast reinforced concrete panel is selected, it is generally 12-15㎝ thick and supported on the precast concrete foundation. Its width is not more than 30㎝, its thickness is not less than 20㎝, and its burial depth is not less than 60㎝ to prevent the effect of foundation frost heave.
2. Level the wall foundation, excavate and level according to the design requirements. Soft soil needs to be compacted or replaced, and compacted to the required density, which should slightly exceed the wall surface.
3. Laying of tendons, the main strength direction of tendons should be perpendicular to the wall, and fixed by pins.
4. Fill the wall with mechanical filling. The distance between the wheel and the reinforcement should be kept at least 15mm. The layer of soil after compaction is about 20-15㎝ thick.
5. During the construction of the wall surface, geotextiles shall be covered at the wall surface to prevent the leakage of filling.