Construction waste improved expansive soil roadbed structure

Abstract

The invention discloses a construction waste improved expansive soil roadbed structure, and relates to the technical field of expansive soil roadbed structures, the construction waste improved expansive soil roadbed structure comprises a road surface protection layer, a transition layer is arranged on the bottom surface of the road surface protection layer, a geogrid A and a geogrid B are arranged on the top surface and the bottom surface of the transition layer respectively, a base layer is arranged on the bottom surface of the geogrid B, and the geogrid A and the geogrid B are arranged on the base layer. A drainage layer is arranged on the bottom surface of the base layer, and an inverted filter layer A and an inverted filter layer B are arranged on the top surface of the drainage layer and the ground respectively; according to the invention, through the high strength and good angularity of the coarse aggregate, the pavement protective layer has excellent wear resistance and can bear the wear effect in the vehicle driving process, and the addition of the fiber reinforced material further improves the toughness of the asphalt concrete and reduces the pavement wear caused by shear force generated by vehicle braking and acceleration.

Claims

1. A construction waste improved expansive soil roadbed structure, characterized in that: include: A pavement protection layer (100), wherein a transition layer (200) is disposed on the bottom surface of the pavement protection layer (100), a geogrid A (201) and a geogrid B (202) are disposed on the top surface and the bottom surface of the transition layer (200), respectively, a base layer (300) is disposed on the bottom surface of the geogrid B (202), a drainage layer (400) is disposed on the bottom surface of the base layer (300), and an anti-filter layer A (401) and an anti-filter layer B (402) are disposed on the top surface and the ground of the drainage layer (400), respectively.

2. The construction waste improved expansive soil roadbed structure according to claim 1, characterized in that: The road protection layer (100) is made of a mixture of asphalt concrete and a small amount of fiber reinforcement material, wherein the coarse aggregate is crushed from hard and wear-resistant rocks, and the particle size is generally between 5 and 20 mm; the fine aggregate is well graded to fill the gaps between the coarse aggregates; the fiber reinforcement material is polyester fiber, the length of which is between 6 and 12 mm, and the addition amount is about 0.1% to 0.3% of the mass of the asphalt concrete.

3. The construction waste improved expansive soil roadbed structure according to claim 1, characterized in that: The transition layer (200) is composed of crushed stone and a small amount of cement material, wherein the crushed stone is limestone with a particle size of 10-30 mm; The cement stabilization material is ordinary silicate cement, and the cement content is about 3%-5% of the mass of the crushed stone. The geogrid A (201) and the geogrid B (202) are made of glass fiber.

4. The construction waste improved expansive soil roadbed structure according to claim 1, characterized in that: The base layer (300) is formed by mixing expansive soil and a construction waste improver, wherein the construction waste improver comprises waste concrete, waste bricks and waste ceramics; the waste concrete is crushed into particles with a particle size of 5-15 mm, the waste bricks are crushed into powder with a particle size of less than 5 mm, and the waste ceramics are processed into fine aggregate; lime, cement and soil solidifier are added to the improver.

5. The construction waste improved expansive soil roadbed structure according to claim 1, characterized in that: The drainage layer (400) is made of open-graded crushed stone, which is composed of crushed stone with a larger particle size of 20-40 mm and a small amount of fine aggregate, and has a porosity of 20%-30%.

6. The construction waste improved expansive soil roadbed structure according to claim 1, characterized in that: The filter layer A (401) and the filter layer B (402) are mainly composed of materials with different particle sizes, and the particle sizes are distributed from coarse to fine along the water flow direction.

7. The construction waste improved expansive soil roadbed structure according to claim 1, characterized in that: The bottom surface of the filter layer B (402) is provided with an isolation layer (500), the bottom surface of the isolation layer (500) is provided with a foundation reinforcement layer (600), cement soil mixing piles (601) are provided inside the foundation reinforcement layer (600), and the top surface of the foundation reinforcement layer (600) is provided with a reinforcement cushion layer (602).

8. The construction waste improved expansive soil roadbed structure according to claim 7, characterized in that: The isolation layer (500) is made of composite geomembrane material, the cement-soil mixing pile (601) is a composite pile body formed by mixing cement and foundation soil on site, the cement content is 10%-20% of the mass of the reinforced soil, and the gravel pile is a pile body formed by filling gravel into the pile hole, and the gravel particle size is between 20-50mm.

9. The construction waste improved expansive soil roadbed structure according to claim 1, characterized in that: Backfill layers (700) are arranged on both sides of the road surface protection layer (100), and the backfill layers (700) include backfill soil (701). A vegetation layer (702) is arranged on the top surface of the backfill soil (701), and a gravel blind ditch (703) is laid on the bottom of the backfill soil (701).

10. The construction waste improved expansive soil roadbed structure according to claim 9, characterized in that: The backfill soil (701) is made of sandy soil material and has a layered structure with each layer thickness not exceeding 30 cm. Each layer is compacted after backfilling.

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