Large deviation in coarse aggregate gradation: At present, the coarse aggregate used in the project is produced by multiple stone factories and transported to the construction site. Each stone factory uses different types of crushers such as hammer, jaw or impact to process crushed stone. In addition, each stone factory does not have strict, unified and standardized production management, and has no unified requirements for the wear degree of production equipment such as crushing hammers and screens. The actual coarse aggregate specifications produced by each stone factory deviate greatly from the requirements of highway construction technical specifications. The above reasons cause the coarse aggregate gradation to deviate greatly and fail to meet the gradation requirements.

Compared with traditional heating methods such as direct heating and steam heating, heat transfer oil heating has the advantages of energy saving, uniform heating, high temperature control accuracy, low operating pressure, safety and convenience. Therefore, since the 1980s, the research and application of heat transfer oil in my country has developed rapidly, and has been widely used in various heating systems in chemical industry, petroleum processing, petrochemical industry, chemical fiber, textile, light industry, building materials, metallurgy, grain, oil and food processing and other industries.
This article mainly discusses the formation, hazards, influencing factors and solutions of coking of heat transfer oil during use.

In the production process of asphalt mixture, there are often some factors that affect its production quality. For example, the bag dust collector of the asphalt commercial concrete station will cause the emission to fail to meet the emission standards due to a large amount of high-temperature gas and dust. Therefore, the dust collector must be treated reasonably and effectively to ensure its normal operation and meet the emission requirements. Bag dust collectors have great advantages, such as strong adaptability, simple structure and stable operation, so they are widely used in the treatment of emissions. However, there are still many shortcomings in bag dust collectors, and effective measures must be taken to maintain them reasonably to ensure their efficient operation.

Pavement preventive maintenance is a periodic mandatory maintenance measure that is taken to restore the service function of the pavement surface when the structural strength of the pavement is sufficient and only the surface function is attenuated. A series of new preventive maintenance technologies such as ultra-viscous fiber-added low-noise micro-surfaces and synchronous gravel seals have been widely used on the main lines of national highways, and the construction results have been widely praised by customers.

Slurry sealing uses mechanical equipment to mix appropriately graded emulsified asphalt, coarse and fine aggregates, water, fillers (cement, lime, fly ash, stone powder, etc.) and additives according to the designed ratio into a slurry mixture and uniformly It is paved on the original road surface and is firmly combined with the original road surface through the processes of coating, demulsification, water separation, evaporation and solidification to form a dense, strong, wear-resistant and road surface seal, which greatly improves the performance of the road surface.

Asphalt mixing equipment (asphalt concrete mixing equipment) all work in open-air sites, with heavy dust pollution. Many parts work in high temperatures of 140-160 degrees, and each shift lasts up to 12-14 hours. Therefore, the daily maintenance of the equipment is related to the normal operation and service life of the equipment. So how to do a good job in the daily maintenance of asphalt mixing station equipment?