Simultaneous gravel sealing technology

Simultaneous gravel seal is the use of special equipment to synchronize the gravel seal car gravel and asphalt cementation materials simultaneously sprinkled on the road surface, the formation of the original road to protect the asphalt gravel wear layer. The sealing layer with high strength, rough surface, non-slip, impermeable, durable, and prevent the rainy days driving fog and so on.

 According to statistics, more than 95% of the roads in Europe are using this technology for conservation, in the country is still a new type of conservation technology. Synchronous gravel seal construction process:
1, requirements: from the perspective of preventive maintenance of asphalt pavement, compared with other technologies, synchronous gravel sealing technology did not put forward higher requirements on the construction conditions, but in order to improve the conservation performance, give full play to this The advantages of new technologies, or need to have certain conditions. First of all, to the road surface damage diagnosis, clear to be the key to repair; fully consider the asphalt binder and aggregate quality standards, such as its wetting, adhesion, abrasion resistance, Technical specifications within the allowable range of paving operations; correct and reasonable choice of materials, to determine the level, the correct operation of paving equipment.
2, synchronous gravel seal construction process:
(1) commonly used structure: the general use of intermittent grading structure, gravel seal stone size used by the strict requirements, that is, the best particle size stone. Considering the difficulty of stone processing and the requirements of non-slip performance of the road, it can be 2 ~ 4mm, 4 ~ 6mm, 6 ~ 10mm, 8 ~ 12mm, 10 ~ 14mm and other 5 files, the more commonly used particle size range of 4 ~ 6mm , 6 ~ 10mm of these two, and 8 ~ 12mm and 10 ~ 14mm two stalls are mainly used for low-grade highway transitional pavement of the lower or middle layer.
(2) According to the road surface roughness and anti-skid performance requirements to determine the particle size range. General road cover for a gravel seal can be, in the road surface roughness that can choose the appropriate size of the stone as the next seal leveling, and then do the seal. Gravel seal as a low-grade highway pavement to be 2 or 3 layers, each layer of stone particle size should be with each other to produce the role of crowding, generally follow the principle of fine on the fine;
(3) before the cover of the original road to be carefully cleaned, the operation process should ensure that a sufficient number of rubber tire roller in order to reduce the asphalt temperature or emulsified asphalt demulsification can be completed in time after rolling positioning process. In addition, the seal can be opened after the car, but in the early should limit the speed, to be completely open after 2h traffic, so as to prevent rapid traffic caused by stone splash;
(4) the use of modified asphalt as a binder, in order to ensure mist spray to form a uniform, equal thickness of the asphalt film, must ensure that the asphalt temperature in the 160 ℃ ~ 170 ℃ range;
(5) The height of the injector of the synchronous gravel seal car is different and the thickness of the formed asphalt film is different (because the fan-shaped asphalt is sprayed with different nozzles), the thickness of the asphalt film is adjusted by adjusting the nozzle height Claim; 
(6) synchronous gravel seal car should be at the appropriate speed of uniform travel, in the premise of the stone and binder material distribution rate must match;
(7) as the surface layer or wear layer of gravel seal, the use of conditions for the original road surface roughness and strength to meet the requirements.
 Simultaneous gravel seal material:
 1, adhesive material. The leading performance of the synchronous gravel seal technology is high, but there is no particular requirement for the application of asphalt. Different asphalt binders can be used, such as softened pure asphalt, polymer modified asphalt, emulsified asphalt, polymer modified emulsified asphalt, diluted asphalt, etc. Thermal asphalt is mainly due to large-scale sealing.
 2, stone. Gravel requires crushing (or hammer crushing) to get the gravel, needle-like stone strictly controlled within 15%, geometric size is better, no impurities and stone powder, crushing value of less than 14%, the stone acid No special requirements, and strictly washed with water.

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