Aggregate base is typically composed of crushed rock capable of passing through a rock screen. The component particles will vary in size from 3/4 inch down to dust.

1. The aggregate base must be compacted properly to ensure road durability.
   骨料基層必須充分壓實以確保道路的耐久性。
2. Engineers tested the aggregate base for quality before paving began.
   在開始鋪路前，工程師測試了骨料基層的質量。