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Building a road
1_______.
Then the ground is leveled. This is done by cutting the top layer until it is flat and level.
2_______. Finally the top layer is added. 3_______. If it is a blacktop road, layers of hot tarmacadam are poured onto the gravel and pressed down using rollers. The total layer of blacktop materials is approximately 300 mm thick. If it is a concrete road, the concrete is laid on top of the gravel. 4_______.
First, the earth is removed using bulldozers and diggers
Next a layer of gravel (approximately 300 mm thick) is spread over the ground
There are two main types: blacktop and concrete
The concrete slabs are usually approximately 250 mm thick and 4.5 m long