Quality requirements for runway foundation
Plastic runway construction is based on asphalt or cement, and the basic practice is roughly the same as road construction. The foundation surface requires good flatness, so as to ensure the consistency of the thickness of the plastic surface layer. The quality requirements for the plastic runway foundation are as follows.
(1) Slope: transverse < 1% (curve 8%, straight 5%, semi-circle 5%), longitudinal < 1%, jump area less than 0.4%, the surface should be smooth, smooth drainage.
(2) flatness: flatness qualified rate of more than 95%, 3 meters straightedge measurement error is not more than 3㎜
(3) Positioning: In order to accurately construct and draw lines, the four semi-circular tangents and two circular centers of the runway site should be firmly and distinctly marked.
(4) Drainage: The drainage system must remove water two hours after a heavy rain. In frozen areas, it is better to add a buffer layer of geotextile between asphalt layer and gravel layer. Special waterproofing should be done along the foundation of the drain trench.
(5) Strength and stability: the foundation should have a certain strength and stability, the surface is uniform and solid, smooth without cracks, no rotten edge pile squeezing, no pockmarked surface, smooth joints without obvious height difference. The cushion is compacted with a density of more than 95%. After being pressed by a medium roller, there are no significant tire marks and loose float soil.
