How to deal with the settlement of asphalt pavement?

The cause of asphalt pavement subsidence is the phenomenon of pavement subsidence caused by vertical deformation of subgrade and pavement. There are usually three situations:

1. Uniform settlement: it is the settlement caused by the further compaction and stability of subgrade and pavement under the action of natural factors and driving. Generally, it will not cause pavement damage.

2. Uneven settlement: the deformation caused by driving under the erosion of water due to the unconsolidated subgrade and pavement and uneven rolling.

3. Local settlement: due to the partial filling of the subgrade is not dense or the subgrade has tombs, dry wells, tree pits, grooves, etc., it will sink due to the erosion of water.

Methods of settlement maintenance:

1. For uneven settlement, if the base course and soil base are dense and stable, only the surface course can be repaired, filled, leveled and compacted with asphalt sand or fine-grained asphalt mixture. If the area is large, the surface course shall be paved.

2. For the local settlement of the subgrade due to pits, grooves, etc., the crushed (gravel) stone, dry masonry or mortar rubble shall be backfilled and compacted again, and the surface course shall be paved after the soil foundation and base course are completely cured.

3. For the settlement of bridge (culvert) head pavement due to false filling, the base course shall be paved, compacted again, and then the surface course shall be made.

4. For soft foundation or cohesive soil layer containing organic matter due to large water content and porosity, soil replacement treatment should be adopted, and its thickness depends on the thickness of soft layer. Gravel soil, gravel soil, medium coarse sand and qualified industrial waste residue shall be used as replacement materials, and the grading shall be reasonable.

5. Depending on the situation, drilling and grouting can be adopted for reinforcement.