The Public Works Department was established in 1854 to oversee construction projects including roads, buildings, railways, flood control, irrigation, and military works. The document then discusses the purpose and types of pavement structures for roads, including flexible pavements made of asphalt and rigid pavements made of concrete. It also describes the construction process for subgrades and different bituminous pavement layers using materials like crushed aggregate, bitumen binder, and compaction.

3. The Public Works Department establish in the
year 1854. At that time PWD was responsible for
the construction of roads,buildings,railways as
well as flood control,irrigation and military
works.The organization’s construction works is
directly connected to the national programme of
development and reconstruction.

4. • PAVEMENT-
Pavement is load bearing and load
distributery component of a road.
• PURPOSE OF PAVEMENT-
1. Load support.
2. Smoothness.
3. Drainage.
4. All weather operation.
5. Direction and guidance.

5. • TYPES OF PAVEMENT STRUCTURE –
Flexible Pavement. (Hot mix asphalt (HMA) pavements)
2. Rigid Pavement. (Portland cement concrete (PCC) pavements)

7. Construction of Subgrade
Materials- Selected Soil , Moorum , Gravel , Aggregate
maximum 50 mm.
Construction Method –
•The subgrade is constructed by spreading the loose soil and
compacting the same at optimum moisture content of the
soil in layer.
•The maximum compacted thickness of each layer is
generally limited to 200 mm as per MORTH.

10. WET MIX
MACADAM
PLANT

12. Construction of Bituminous
Pavement layers
Three types of bituminous layers-
1. Bituminous Macadam.
2. Penetration Macadam.
3. Bult up spray Grout.

13. It consist of crushed aggregate and bituminous
binder heated and mixed in a hot mix plant at
specified temperature , transported to the
construction site, laid with a mechanical pawer
and compacted by roller.
Material used : Bitumen binder of grade VG -
30,20 and Max size of aggregate 50mm.

14. Bituminous Penetration Macadam Base
Course
The coarse aggregate of specified size are
first spread and compacted well in dry
state. Compected thickness 50-75 mm.
After compacting of dry aggregates, hot
bituminous binder of specified grade is
spread in large quantity on the top of this
layer. Filling up a part of void and
binding by key aggregate.

15. It consist of a two layer composite construction
of compacted crushed stone aggregate with
bituminous binder applied after each layer and
key aggregate placed on the top surface of the
second layer.

16. Submitted By
Mr. Deepak Bhatt
Submitted to :
Mr. Jaibeer Chand
U.I.T Dehradun