Asphalt

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Asphalt

What is Asphalt?

Asphalt, A mixture of bitumen binder and aggregates used for paving roads, roofs, and waterproofing.

Description

Asphalt is a dark, viscous binder derived from the refining of crude oil. Combined with sand and gravel, it forms hot mix asphalt (HMA) for roadways, parking lots, and driveways. Roofing asphalt is oxidized and blended with mineral stabilizers to create shingles and roll roofing. Key performance factors include penetration grade, viscosity, and polymer modification for rut resistance. Placement temperature, compaction, and joint density all contribute to determining pavement longevity.

FAQs

  • What is hot mix asphalt?

    Aggregates blended with hot bitumen at 275–325°F for paving.

  • How thick is a residential asphalt driveway?

    Typically 2 in compacted HMA over 4 in aggregate base.

  • What causes asphalt rutting?

    High temperatures, heavy loads, or inadequate compaction.

  • How is asphalt recycled?

    Reclaimed asphalt pavement (RAP) is milled, reheated, and mixed into new HMA.

  • Are asphalt shingles fire rated?

    Class A fiberglass shingles meet the highest rating.

  • Who specifies asphalt grades?

    Departments of transportation and ASTM D 946 penetration specs.

  • What is polymer-modified asphalt?

    Bitumen enhanced with SBS or EVA polymers for elasticity and crack resistance.

Fun Fact

Fun Fact: The ancient Babylonians used naturally occurring asphalt to waterproof ziggurat foundations over 3,500 years ago.

CSI Code

32 12 16

NAHB Code

270