1. Road Construction Technology
December 2014
Road Construction Technology
Prepared by- Er. Dipesh Pandey

2. CONTENTS
Introduction Activities in Road Construction Tools, Equipment and Plant Earthwork Mass Haul Diagram

3. Definition
Activities to change existing ground to designed shape, grade and provide necessary facilities for smooth, safe and efficient traffic operation, including reconstruction of existing road.

4. Activities in Road Construction
Earthwork
site clearance,
E/W in filling,
E/W in excavation,
Excavation for borrow pit,
Excavation for foundation,
Disposal of surplus
Structural Work
Earth retaining str,
Gully control works,
Land slide stabilization,
River training works,
Bridge protection works
Pavement Work
Sub grade preparation,
Sub-base,
Base course and
Wearing course
Miscellaneous Work
Road Ancillaries
Traffic sign/signal, markings
Boi-engineering works
Drainage Work
Side drains,
Culverts,
Sub surface drain,
Causeway
Minor bridge

5. Tools, Equipment and Plant
Hand shovel,
Chisel, Peak,
Spade,
Hand Rammer,
Brushes,
Trowel,
Wheel Borrow
Equipment
Earth Moving Equipment
Dozer, Scraper, Loader, Excavator, Backhoe, Dragline, Clamshell, Trench digger
Leveling Equipment
Motor Grader
Paving Equipment
Binder storage tank with heating device, binder spreader, aggregate spreader, cement concrete mixture, bituminous mechanical paver, cement concrete paver
Compaction Equipment
smooth wheel roller, vibrating roller, pneumatic roller, sheep foot roller, different capacity rammers

6. Cont.… Transporting Equipment Lifting Equipment Loader, Backhoe,
Dumping trucks,
Flat body trucks,
mini dumper
Lifting Equipment
Loader,
Backhoe,
Different capacity crane
Leveling Equipment
Motor Grader
Paving Equipment
Binder storage tank with heating device, binder spreader, aggregate spreader, cement concrete mixture, bituminous mechanical paver, cement concrete paver
Miscellaneous Equipment
Rock driller,
Core Cutter,
Edge cutter

7. Cont.…. Plants Cement concrete plant, Asphalt concrete plant,
cold mix plant,
Aggregate crushing plant,
Screening plant,

8. Earthwork
Process to prepare sub grade level bringing it to design grade and shape
may be in embankment and filling
Quantity based on longitudinal and cross section
Mass haul diagram necessary to decide economic haul
E/W quantities are estimate based on L and X sections

9. Site Clearance
Started just after survey works and before any construction works
Clearing of grass, weeds, bushes, shrubs
Removal of existing trees, stumps and roots along the
road alignment
Removal of existing structures along right of way

10. Earthwork in Filling Reasons:
Necessary when we have to raise the sub-grade from existing ground level
Reasons:
To keep sub-grade high from ground water table
To prevent damage due to surface and capillary rise
To maintain vertical alignment

11. Design elements:
Height,
Fill material,
Settlement,
Stability of foundation,
Stability of slope
Equipment:
Grader, Roller, Tripper and water tanker or manually for small project

12. Construction steps:
Laying layer by layer
Grading each layer
Attaining desired density before next layer is placed
The thickness of the layers may vary between
10 to 30 cm depending on various factors such as soil type, equipment, specifications etc.
Quality Control
Checking of suitability of filling material
Checking of field moisture and dry density of each layer (> 93 % for below and > 95% for above)
Proper finishing of formation slope as per design

13. E/W in Excavation
In the process of cutting or loosening and removing earth including rock from its original position, transporting and dumping it as a fill or spoil bank.
Also includes excavation for side drains
Earth excavation work may be divided as excavation or cutting, grading and compaction.

14. Design Elements Equipment Depth, Stability of foundation,
Stability of slopes,
Accommodation of road side drain
Equipment
Grader, roller, tipper and water tanker

15. Construction Steps Quality Control Excavation
Grading of sub-grade layer
Compaction with roller
Quality Control
Fixing reference pegs
Checking field moisture and dry density
Proper finishing of formation slopes

16. Field Control of compaction
Measurement of moisture content
Measurement of max. dry density corresponding to optimum moisture content

17. Planning of E/W Mass haul Diagram
Earthwork for a highway project involves cuts and fills.
The most balanced design is one which utilizes the cut volumes in the adjacent fills.
This is achieved by a mass haul diagram which is a graphical representation of amount of cut and the fill and the manner in which the earth is to be hauled from cut to fill.

19. Planning of E/W
Mass haul Diagram
The ordinate at any station along the MHD indicates the earthwork quantity accumulated up to that point, and is the summation of the differences between cut and fill.
The maximum (+) ordinate indicates a change from cut to fill (D) and the minimum (-) ordinate indicates from fill to cut (A and G).
Upward sloping curves indicate (rising left to right) indicate a cut
Downward sloping (falling left to right) curves occur in a fill section
peaks indicate a change from cut to fill and valleys occur when the earthwork changes from fill to cut

20. If the curve has steep slope it indicates heavy cuts or high fills
If the curve has steep slope it indicates heavy cuts or high fills. Flat slopes indicate small earthwork quantities.
The balance point is defined as a point where the volume in excavation balances the volume in embankment.
Any line drawn parallel to the base line and intersecting two points within the same curve indicates a balance of cut and fill between these two points ( C and D). Such a line (HJ) is called a balancing line.

21. Haul: it has dual meaning
Haul: it has dual meaning. Distance over which material is moved and also the volume distance of material used.
Free haul: The certain amount of haulage is included in the earthwork rate itself and the contractor is expected to carry earth over this haulage within his quoted rate.
Over haul: the haulage over the free haul distance paid for extra rate called over haul.

22. Economic over haul: the economic over haul distance can be determined by equating the cost of roadway excavation plus overhaul and tipping in embankment with the cost of borrow pit material plus excavation, haul and wasting of roadway material within the free haul distance
a= cost of roadway excavation per cu. m.
b= cost of overhaul and tipping per cu. m.
c = cost of borrow material per cu. M.
L= economic overhaul distance in stations
a + b x L = c + a
L= c/b

23. Thank you