The document discusses reinforced concrete deck girder bridges (rcdg), outlining their structure consisting of horizontal beams supported by piers, with limitations in span length due to flexural weakness. It details the main components including the girder, bearings, pier caps, piers, and pile foundations, emphasizing their roles in load transfer and support. Additionally, it highlights the bridge deck's function in supporting vertical loads from traffic while maintaining structural integrity.

1. Reinforced Concrete Deck
Girder Bridge
(RCDG Bridge)

2. Materials for Construction

3. Girder / Beam Bridge
The most common and basic type.
Consists of a horizontal beam supported at
each end by piers.
The weight of the beam pushes straight down
on the piers.

4. Typical Beam / Girder Bridge

5. Girder / Beam Bridge
The farther apart its piers, the weaker the beam
becomes. This is why beam bridges rarely span
more than 250 feet.

7. Forces:
When something pushes down on the beam, the
beam bends. Its top edge is pushed together, and its
bottom edge is pulled apart.

8. Bridge Deck
The principal function of a bridge deck is to
provide support to local vertical loads (from
highway traffic, railway or pedestrians) and
transmit these loads to the primary
superstructure of the bridge.

9. Bridge Deck
As a result of its function, the deck will be
continuous along the bridge span and (apart
from some railway bridges) continuous across
the span. As a result of this continuity, it will act
as a plate (isotropic or orthotropic depending
on construction) to support local patch loads.

10. Link for short video presentation:
https://youtu.be/lBP7739C83s?t=39s

11. Now let us discuss the
Five major parts of a
Reinforced Concrete
Bridge
1.Beam/Girder
2.Bearing
3.Pier Cap/ Headstock
4.Pier
5.Pile cap and Piles

12. Beam / Girder
Beam or girder is that part of superstructure structure
which is under bending along the span. it is the load
bearing member which supports the deck.
Span is the distance between points of support (eg piers,
abutment).
Deck is bridge floor directly carrying traffic loads

13. Prestressed I Girder

14. Steel Bridge Beam Girders

15. Bearing
Bearing transfers loads from the girders to the pier
caps. Bearing is a component which supports part of
the bridge and which transmits forces from that part to
another part of the structure whilst permitting angular
and/or linear movement between parts.

16. Laminated
Elastomeric
Bearings

17. Pier Cap / Headstock
Pier Cap / Headstock is the component which
transfers loads from the superstructure to the piers.
Pier cap provide sufficient seating for the Bridge
girders and disperse the loads from the bearings to
the Piers.

18. RC Pier Cap

19. Pier
Pier is that part of a part of the substructure which supports the
superstructure at the end of the span and which transfers loads on the
superstructure to the foundations.
Depending up on aesthetics, site, space and economic constraints various
shapes of piers are adopted to suit to the requirement.
Mostly Reinforced Concrete or Prestressed concrete are adopted for the
construction of piers.
Piers are compression members. Depending on the loading and bearing
articulations, piers may be subjected to bending as well.

20. Bridge Pier Substructure

21. Pile cap and Piles
Pile foundation is the most commonly used foundation system
for bridges.
Pile is a slender compression member driven into or formed in
the ground to resist loads.
A reinforced concrete mass cast around the head of a group
of piles to ensure they act together and distribute the load
among them it is known as pile cap.

22. Completed pile cap rebar framing

23. General Span Types

24. Comparison Between Concrete
Bridges

26. RC Slab Bridge

28. RCDG Bridge

30. PCDG Bridge

32. No. of Bridge Girders – No. of Lanes