General Terms used in Earthwork of Roads

1. Borrow Pits2. Balancing Earthwork3. Lead & Lift4. Spoil Bank

Borrow PitsSmall pits dug parallel to the road alignment

on both sides of the road formation to draw extra earth required to fill in embankment.

Spoil BankExtra earth excavated and to be dumped on

the road sides in road in cutting.Dumped in regular shape for future use.

Balancing EarthworkWhile constructing road, it is desirable for a

segment of road, that the quantity of earthwork in cutting and embankment should be nearly equal if the soil available is good for the use.

If possible, keeping in mind the limiting values of gradients and curves, the alignment is so fixed to have the equal quantity of earthwork in cutting and banking.

This is known as balancing earthwork.

Lead & LiftLead: Horizontal distance travelled by the

earth to be moved for banking or dumping.Lift : Vertical distance travelled by the

earthwork after excavating.

Construction Procedure for Earthen RoadPreparation of Sub-Grade: Arranging sub-

grade in proper gradient & camber.The sub-grade is rolled & watered to have

OMC & compacted to MDD.Over it, a layer of soil 10cm thick is sprayed,

rolled, & finished to have required camber & gradient.

4-5 days curing.Opening to traffic.Watering for 10 days after opening to traffic.

Sub-Grade

Soil Layer 10 cm Thick

Marking Road Levels & BoundariesMarking the centre line of alignment on

ground with the help of theodolite.Marking carriageway, shoulder, berms,

borrow pits & road boundaries.Putting pegs & clearing stakes in the sides &

cleaning the area within the clearing stakes.

Construction StepsClearing & Grubbing: It includes removing

any unwanted material i.e. tree roots, grass, loose soil, Preparing the leveled surface

Stripping off the top of soil to avoid the plant growth on the road.

Excavation: if the existing material is not suitable for the road, other suitable material is dumped in the excavated portion.

Embankment preparation

Sheep Foot Roller