What are the main components of hot mix asphalt (HMA)?

Hot mix asphalt consists of aggregates (coarse, fine, mineral filler - 94-96% by weight) bound by asphalt binder (bitumen - 4-6% by weight). Aggregates provide structural strength, stability, and skid resistance. Asphalt binder (derived from petroleum) waterproofs, binds aggregates, and provides flexibility. Mix design optimizes aggregate gradation, binder content, and air voids (typically 4%) for durability, stability, and workability. Additives like polymers may enhance performance.