Geogrid, geocell, geotechnical materials welding principle geogrid is used for roadbed reinforcement, so that the granular filler and mesh interlock together to form a stable plane to prevent the subsidence of the subsidence The vertical load can be scattered and scattered, and the geographically harsh areas can be multi-layered; 2. Spreading in the dam and roadbed filling can increase its stability and reduce the floor space; 3. For road reinforcement, The mesh and pavement materials can be blended together to effectively distribute the load and prevent cracks on the road surface; 4. Can withstand certain impact loads; 5. Can withstand large alternating loads; 6. Shorten the construction period; 7. It can also be constructed under harsh environmental conditions; 8. It can prevent road surface subsidence and crack caused by tumbling; 9. It can reduce the amount of pavement material; 10. Speed up construction.
Geogrid can be used for road and dam soft soil consolidation and desert reconstruction. It is a shortage of plastic products in Xinjiang. The total investment of this set is more than 8 million yuan, which is invested by PetroChina Co., Ltd. 60%, and Urumqi Petrochemical Investment 40%. The set has an annual output of 2,500 tons of single and two-way tensile geogrid. Previously, the plant had successfully commissioned the largest set of geomembrane installations in the northwest in April this year. The total investment of the two sets of equipment was 32 million yuan. At present, the geomembrane plant has produced 400 tons of products, which have been used in large landfills in Karamay and Dushanzi after being put on the market.
a) pavement paving.
Since the old cement concrete pavement and the newly widened concrete pavement are poured along the slope of the old cement concrete pavement, the flatness of the surface is better, but due to the asymmetry of the concrete pavement, the road arch is adjusted. The asphalt pavement on both sides of the road arch is not the same thickness, the thinnest is 7cm, and the thickest is 15cm. Therefore, asphalt gravel is used as the asphalt concrete leveling layer. After the leveling layer is paved, the surface layer is paved.
(2) Geogrid technical requirements
1. The thickness of the geogrid should be thin, generally about 3.0mm, in order to spread;
2. The size of the grid grid should be 0.5 to 1.0 times the aggregate size. This project uses 25.4×25.4mm;
3. The tensile strength of the geogrid should be selected to be large, the longitudinal direction is greater than or equal to 50KN/M, the lateral direction is greater than or equal to 50KN/M, and the deformation resistance is strong;
4. Elongation is less than 4%;
5. The amount of glue is greater than or equal to 20%;
6. The geogrid is self-adhesive, with a width of 2m and a temperature resistance of -100 to 280 degrees Celsius.
(3) paving geogrid
1. Applying a layer of emulsified asphalt on a cleaned cement concrete pavement with a small asphalt spreader at 0.5 kg/m2 with a width of 2.0 m;
2. Spraying a layer of emulsified asphalt at a temperature above 10 ° C when the road surface is not wet;
3. After spraying the adhesive layer emulsified asphalt, the geogrid laying is started when the asphalt to be bonded has been broken. After the geogrid is laid, a light-duty rubber roller is used to moderately press it to ensure that the geogrid has good adhesion to the original road surface.
4. The geogrid paving equipment is used to manually lay the geogrid once. For unevenness, apply the spreader to flatten. If you encounter a curve, cut the geogrid inside the curve with shear force, then flatten one side, apply asphalt, and then cover the other side. When lap jointing, it should be smooth and longitudinally and horizontally tensioned.
5. After a roll of geogrid is finished, another geogrid adhesive layer is sprayed. Laying of geogrid during laying: longitudinal distance not less than 15 cm, lateral distance not less than 10 cm; to sprinkle 20 cm of asphalt belt on the former geogrid, and then spread the second e s. According to this process sequence, the geogrid of half of the road surface is covered, and the width of the road surface is 20 cm beyond the width of the road surface so as to be pressed against the geogrid of the second road surface.
(4) paving asphalt concrete
1. In order to facilitate the car to walk on the geogrid and the sprayed asphalt road without driving the geogrid, after paving the geogrid on half of the road, sprinkle 5mm of stone powder.
2. At the beginning of the geogrid, it is to be fixed with iron nails and sprinkled with a layer of adhesive asphalt.
3. It is forbidden to brake, turn, or turn the car on the geogrid.
4. When the geogrid is pulled up by the car, it should be flattened with the spreader immediately.
5. Asphalt concrete pavement is paved with asphalt concrete pavers.
Five, test road detection
1. Deflection measurement. After the test road was paved, the BZZ-100 standard car and the 5.4 m long rod deflection instrument were used to measure the deflection value of the concrete pavement every 50 m.
2. The real side deflection and the average deflection are L=11.50 mm, and the mean square error δ=2.21, which means that the deflection is L==114.
3. According to the theoretical calculation, add 10cm asphalt concrete on the old road (δ=0.330mm), calculate the deflection to reach 0.24mm, add a layer of geogrid to calculate the deflection value can reach 0.14mm, which is equivalent to an increase of 8cm thick. Asphalt concrete, measured data shows that the point of >0.10mm accounts for 2.8%; the point of ≥0.15mm accounts for 2%, and the point of ≥0.30 accounts for 1.1%. The above data shows that the addition of geogrid in asphalt concrete is obvious.
February 02, 2020
