Dirt, stone, gravel and maybe some wood for that bridge across the creek.

The challenge with Gravel is dust generation.

Mix a little cement in it and let it set up. Crushed lime stone will accomplish about the same thing.

Crushed stone, crushed shells, cobblestones, bricks.

Further explanation is required I see.

Road will be used by heavy Trucks(20 Ton),driving on a maximum speed limit of 40KM/h

• Roads north of the Arctic Circle region can be made of frozen rivers.
• The Russian railway system has access to design manuals for constructing railways across frozen lakes.

To answer this effectively we need to know where you are, the climatic history, what raw materials are available, encountered soil types along the road route (these may vary greatly), type of truck wheels & arrangements, maximum truck axle load, and the maximum number of vehicle passes per day.

It's not as simple as slapping down some dirt or gravel if you want it to last a month or a season.

¾ North of South Africa.

¾ Clay type of Soil.

¾ Generally temperate climate, due in part to being surrounded by the Atlantic and Indian Oceans on three sides, by its location in the climatically milder southern hemisphere.

¾ Iron ore, Coke and Coal, Ferro Alloys Scrap for steel making, Pig iron are available as raw material

¾ Heavy Mobile equipments (Tyre, steel wheels)

¾ 40 Ton Maximum Load

¾ 100 Vehicles per day

If your running heavy equipment with steel wheels down it. I wouldn't put anything more the crush and run down. They will damage a good road surface. The complaint i see is dust from the traffic. Run a water truck and spray it to keep the dust down.

Hire a consultant locally.