The phenomenon of temperature segregation in asphalt concrete paving

The so-called asphalt concrete temperature segregation refers to the original by fully mixing, uniform temperature of asphalt mixture, after a certain process, the temperature of a big difference.

In asphalt paving operation, asphalt concrete has certain temperature in order to ensure the paving quality. The asphalt concrete mixing station according to the provisions of the material composition, heating and stirring, refined asphalt mixture by the dump truck to the paving site, it should be said that the mixing station supply truck is to meet the quality requirements, there is no gradation segregation, no segregation temperature. However, in asphalt pavement construction, there is widespread temperature segregation of asphalt mixture, but also quite serious.

The developed countries have done a lot of research on the temperature interest of asphalt concrete. Such as the United States tech company ACE (Astec) using high precision infrared cameras for paving shooting, found temperature segregation degree than people expected much larger: asphalt mixture into the dump 143 c card book, the distance is only 16~24km, arrived at the paving site, the difference in temperature of asphalt mixture actually reach 44 degrees, some areas of the paving surface temperature on the unexpectedly low to 99 DEG C. In 1997, Australia, a building contractor from 278km away material transport, arrived at the construction site, the temperature of material on both sides of the truck is only 88 degrees Celsius, the temperature at the top of the car is 96 DEG C, and the temperature is 152 DEG C is still the middle of the car.

In China's highway construction, most of the asphalt mixture transport vehicles are less than 10t deadweight trucks, load capacity is less than half of developed countries. Drivers in order to facilitate the trouble, the bucket of material basically do not cover. All this will aggravate the local material cooling in the vehicle, causing serious temperature segregation. Therefore, although our country has not done any special research in this field, we can say with certainty that the segregation of asphalt mixture in the road construction is much more serious than in developed countries.