How to construct geogrids on high-grade highways and airport pavements?

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How to construct geogrids on high-grade highways and airport pavements?

Currently, there are two types of commonly used geogrids: with and without self-adhesive adhesive. Those with self-adhesive adhesive can be directly laid on the leveled base layer, while those without self-adhesive adhesive are usually fixed with nails.

Construction site:

It is required to compact, level, and remove sharp protrusions. Grid laying; On a flat and compacted site, the main stress direction (longitudinal) of the installed and paved grid should be perpendicular to the direction of the embankment axis. The laying should be smooth, without wrinkles, and should be tensioned as much as possible. Fixed with dowels and earth and stone ballast, the main stress direction of the laid grid should preferably be the full length without joints, and the connection between the widths can be manually bound and overlapped, with the overlapping width not less than 10cm. If the grid is installed in more than two layers, the joints between layers should be staggered. After laying a large area, the overall flatness should be adjusted. After covering a layer of soil, before rolling, the grid should be tensioned again using manual or machine tools, with uniform force, so that the grid is in a straight stress state in the soil.

Selection of filler:

The filler shall be selected according to the design requirements. Practice has proven that except for frozen soil, swampy soil, household garbage, chalk soil, and diatomite, all of them can be used as road materials, but gravel soil and sand soil have stable mechanical properties and are slightly affected by the amount of water required, so they should be preferentially selected. The particle size of the filler shall not be greater than 15cm, and attention shall be paid to controlling the grading of the filler to ensure the compaction weight.

Spreading and compaction of fill material:

After the grid is laid and positioned, it should be filled and covered in a timely manner. The exposure time should not exceed 48 hours. The flow process method of laying and backfilling can also be adopted. Pave road fillers at both ends of the beach first, fix the grid, and then advance towards the middle.

The rolling sequence is from both sides to the middle. During rolling, the roller shall not be in direct contact with the reinforcement material, and vehicles are generally not allowed to drive on uncompacted reinforcement bodies to avoid dislocation of the reinforcement material. The layer compaction degree is 20-30cm. Compaction must meet the design requirements, which is also the key to the success of reinforced soil engineering.

Waterproof and drainage measures:

In reinforced soil engineering, it is necessary to do a good job of drainage treatment inside and outside the wall; Do a good job of foot protection and erosion prevention; Filter and drainage measures shall be provided in the soil, and geotextile shall be provided if necessary.

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Post time: Feb-21-2023