China Naming Network - Solar terms knowledge - What happened to the asphalt pavement that was overloaded and lost fine materials? It has just been laid for six days.

What happened to the asphalt pavement that was overloaded and lost fine materials? It has just been laid for six days.

Generally, it is due to heat expansion and cold contraction, but it naturally falls off.

1, poor asphalt quality: asphalt quality plays a key role in the road performance of asphalt mixture. If the performance of asphalt is poor, such as low consistency, high wax content and poor adhesion, there will be no firm adhesion between asphalt and aggregate, and the adhesion between particles will decrease, which will eventually make the asphalt mixture loose and peel off.

2. Insufficient adhesion between coarse aggregate and asphalt: The adhesion between coarse aggregate and asphalt material greatly affects the strength and durability of asphalt mixture. Generally speaking, the adhesion between alkaline aggregate and asphalt is good, but in acidic rocks, the adhesion between mineral aggregate and asphalt often fails to meet the requirements.

3. The hydrophilicity coefficient of mineral powder is too large: it is required that mineral powder is loose and dry in asphalt mixture, and in order to make mineral powder have good adhesion with asphalt, the hydrophilicity of mineral powder is required to be small.

4. Poor cleanliness of fine aggregate: At present, fine aggregate commonly used in asphalt mixture includes stone chips and machine-made sand, and its cleanliness is mainly characterized by sand equivalent. The lower the equivalent of sand, the more dust is contained in the fine material. When this kind of fine material is mixed into asphalt mixture, it will lead to the decline of cement adhesion and lead to diseases such as looseness.