1、This machine grinds out the crushed rock ready for road building.
這臺機(jī)器碾碎用來筑路的石頭。

2、Coarse gravel or crushed rock laid to form a bed for roads or railroads.
支撐公路或鐵路的用泥土或巖石做成的路基。

3、The slag heaps hold massive dumps of crushed rock discarded after gold extraction.
礦渣堆由金礦挖掘后遺留下來的大量碎石所組成。

4、Coarse gravel or crushed rock laid to form a bed for roads or railroads
道碴用來鋪公路或鐵路路基的粗砂礫或碎石

5、Macadam type bases involving successive layers of crushed rock bound with rock dust were also used.
人們曾經(jīng)使用“石結(jié)”基層——幾層由石粉黏結(jié)在一起連續(xù)的碎石層。