What is the optimal temperature range for asphalt paving?

Urban trunk roads, expressways.

When the construction temperature is lower than 10, or when the construction temperature of other grades of road construction is lower than 5, it is not suitable for construction. Paving asphalt mixture.

It should be slow, even, and continuous and uninterrupted. Mixtures paved mechanically shall not be trimmed manually.

The temperature of the initial pressure link is generally maintained at 110-140 degrees Celsius.

Between. The temperature of the recompression link of the road surface should be kept at 120-130 degrees Celsius. The temperature at the end of the final pressure should be greater than 90 degrees Celsius.

Asphalt spreading temperature should be determined according to the construction temperature and asphalt number, in general, petroleum asphalt should be 130 170, coal asphalt should be 80 120, emulsified asphalt.

It should be spread at room temperature.

After paving, the rolling process is immediately followed, and the compaction is divided into three stages: initial pressure, double pressure and final pressure (including forming). The rolling temperature is 110 140 during normal construction, and not less than 110; Low temperature construction rolling temperature 120 150. The final temperature of rolling is not lower than 65 80.

The optimal temperature for asphalt paving needs to be determined according to the type of asphalt concrete being paved. The common No. 70 asphalt concrete is: normal construction: 135, low temperature construction: 160.

The temperature of the initial pressure link is generally maintained between 110 and 140 degrees Celsius. The temperature of the recompression link of the road surface should be kept at 120-130 degrees Celsius. The temperature at the end of the final pressure should be greater than 90 degrees Celsius.

Asphalt spreading temperature should be determined according to the construction temperature and asphalt number, in general, petroleum asphalt should be 130 170, coal asphalt should be 80 120, emulsified asphalt should be dispersed at room temperature.

The asphalt concrete paving temperature needs to be determined according to the type of asphalt concrete being paved. The common No. 70 asphalt concrete is: normal construction: 135, low temperature construction: 160.

Asphalt concrete (bituminous concrete) is commonly known as asphalt concrete, which is a mixture of ore with a certain gradation composition, crushed stone or crushed gravel, stone chips or sand, mineral powder, etc., and a certain proportion of road asphalt materials.

According to the different types of aggregates used, it can be divided into several categories of gravel, gravel, sandy and slag, and crushed stone is the most common. According to the maximum particle size of the mixture, it can be divided into coarse grains (below 35 40 mm), medium grains (below 20 25 mm), fine grains (below 10 15 mm), sand particles (below 5 7 mm) and so on.

1. Asphalt pavement has high temperature stability.

High-temperature stability is the ability of asphalt pavement to resist flow deformation. Because the strength and stiffness of asphalt pavement decrease significantly with the increase of temperature, in order to better ensure that asphalt pavement will not produce diseases such as waves, shifts, ruts, and congestion under the repeated action of driving load in high temperature season, asphalt pavement should have good high temperature stability.

2. Asphalt pavement has low temperature crack resistance.

Low-temperature crack resistance refers to the ability of asphalt pavement to resist low-temperature shrinkage cracks. As the asphalt pavement decreases with temperature, the stiffness increases, and the expansion capacity decreases.

Under the action of external load, so that part of the stress has no time to relax, the stress gradually accumulates, and these accumulated stresses exceed the tensile strength of the material when cracking, which will lead to the destruction of the pavement, so the asphalt pavement should have lower stiffness and greater deformation resistance at low temperature to meet the low temperature crack resistance.

3. Asphalt pavement has water stability.

Water stability refers to the ability of asphalt pavement to resist the erosion of water and gradually produce asphalt membrane peeling, granulation, loosening, and potholes. This is due to the presence of moisture on the one hand to reduce the cohesion of the asphalt itself, but also to destroy the asphalt pavement between the cohesion between the asphalt and the mineral material, thereby accelerating the spalling phenomenon and causing water damage to the road.

When the construction temperature of urban expressways and main roads is lower than 10, and the construction temperature of other grades of roads is lower than 5, it is not suitable to pave and roll hot-mixed asphalt mixture.

Wind, snow and rain do not allow hot-mix asphalt mixture pavement construction.

When the sun is sunny and the temperature is low, the following measures must be taken for construction:

Increase the temperature of transporting, paving and rolling the mixture. The ordinary transportation temperature is not less than 150 and not more than 175; Paving low temperature construction temperature is 130 140; The rolling temperature should be 135 150, and not less than 110, and the final rolling temperature should not be less than 70 80. The transportation temperature of modified asphalt mixture shall not be less than 170, and shall not exceed 185; Paving low temperature construction temperature is 140 160, rolling low temperature construction temperature 135 150;

The material truck must be covered with thermal insulation measures;

Using a high-density paver, the screed should be heated;

Strengthen the temperature measurement work at the construction site and make a good temperature measurement record;

Shorten the paving time, press with the spread, and do a good job of construction joint treatment.

What is the temperature of ordinary asphalt mixture factory, arrival and paving?

The temperature of the construction is mainly determined according to the asphalt marking! No. 50 asphalt: asphalt loss to let the heat temperature 160 170 degrees, asphalt mixture discharge temperature 150 170 degrees, mixture waste temperature higher than 200 degrees, transportation to the site not less than 150 degrees, normal paving temperature 140 degrees, low temperature paving not less than 160 degrees, normal temperature when the start of rolling is not less than 135 degrees, low temperature when the internal temperature is not less than 150 degrees, the surface temperature of the drum roller rolling is not less than 80 degrees, tire roller 85 degrees, The vibratory roller is 75 degrees, and the road surface temperature for open traffic is not higher than 50 degrees.

No. 70 asphalt, asphalt heating temperature 155 165 degrees, mixture discharge temperature 145 165 degrees, mixture waste temperature is higher than 195 degrees in Jiankong, transportation to the site is not less than 145 degrees, normal paving temperature of mixture is not less than 135 degrees, low temperature paving temperature is not less than 150 degrees, the internal temperature of the mixture at room temperature is not less than 130 degrees, low temperature is not low than 145 degrees, the surface temperature of the final rolling drum roller is not less than 70 degrees, tire roller is not less than 80 degrees, The vibratory roller is not lower than 70 degrees, and the surface temperature of open traffic is not higher than 50 degrees! ​

The paving temperature of asphalt pavement, the temperature of initial pressure, re-pressure and final pressure hail is 135 -175 respectively; 130°-140°；Not less than 80; The temperature is greater than 80.

1) Initial pressure: Immediately after paving (high temperature rolling), completed with a static two-wheel roller (2 times), the initial pressure temperature is controlled at 130°-140°.

It is best not to use tyre rollers, as the temperature is high and it is very easy to produce deep tyre marks and asphalt push. The maximum thickness of the compacted layer of asphalt concrete should not be greater than lo0mm, and the thickness of the compacted layer of asphalt stabilized gravel mixture should not be greater than 120mm, but when a high-power roller is used and the degree of compaction is proved to be able to be reached by the test, it is allowed to increase to 150mm.

2) Re-pressing: Re-pressing is carried out immediately after the initial pressure, and the vibration roller and tire roller are used for re-pressing (the plastic wheels of this tire roller do not have the anti-friction edges of ordinary plastic tires, and its surface is smooth.

For the mixture with a large particle size dominated by coarse aggregates, especially the large particle size asphalt stabilized gravel base, it is advisable to give priority to the repressing of vibrating rollers. Thin asphalt layers with a thickness of less than 30mm should not be rolled by vibrating rollers.

3) Final pressure: The final pressure is carried out immediately after the repressing, and the final pressure is rolled by a two-wheel steel cylinder roller that turns off the vibration to eliminate the wheel track (the final temperature is greater than 80).