Brief details about different types of road and railway bridges with their images.

1. BRIDGES
BY SANSKAR SHARMA

2. ~ TYPES OF ROAD BRIDGES :
➡ SIMPLE OR BEAM BRIDGES
➡ CONTINUOUS BRIDGES
➡ ARCH BRIDGES
➡ CANTILEVER BRIDGES
➡ SUSPENSION BRIDGES

3. ➡SIMPLE OR BEAM BRIDGES
Beam bridges, also known as
stringer bridges, are the simplest
structural forms for bridge spans
supported by an abutment or pier
at each end. No moments are
transferred throughout the
support, hence their structural
type is known as simply
supported.

4. ➡CONTINUOUS BRIDGES
The continuous span gives beam
bridges the ability to span great
distances. A single beam bridge
rarely spans more than 250 feet.
But, as in the Chesapeake Bay
Bridge-Tunnel, several beam
bridges can be linked together,
creating what is called a
continuous span.
The world's longest bridge is a
continuous span beam bridge.
Almost 24 miles long, the Lake
Ponchartrain Causeway consists of
two, two-lane sections that run
parallel to one another.

5. ➡ARCH BRIDGES
An arch bridge is a bridge with
abutments at each end shaped as
a curved arch. Arch bridges work
by transferring the weight of the
bridge and its loads partially into
a horizontal thrust restrained by
the abutments at either side.

6. ➡CANTILEVER BRIDGES
A cantilever bridge is a bridge built
using cantilevers, structures that project
horizontally into space, supported on
only one end. For small footbridges, the
cantilevers may be simple beams;
however, large cantilever bridges
designed to handle road or rail traffic
use trusses built from structural steel, or
box girders built from prestressed
concrete. The steel truss cantilever
bridge was a major engineering
breakthrough when first put into
practice, as it can span distances of
over 1,500 feet (460 m), and can be
more easily constructed at difficult
crossings by virtue of using little or no
falsework.

7. ➡SUSPENSION BRIDGES
The phrase suspension bridge is a
polyseme, used to describe a
group of bridges that includes
various types of suspension
bridges, and one sub-group
within this, being the best-known
type, that encompasses bridges in
which the deck is hung below
suspension cables on vertical
suspenders.
Theoretically , the suspension
bridges can be constructed to
span of 3000 m .

8. ~TYPES OF RAILWAY BRIDGES :
➡ IRON AND STEEL BRIDGE
→ STEEL GIRDER BRIDGE
→ STEELTRUSS BRIDGE
→ CONTINUOUS STEEL BRIDGE
→ STEEL CANTILEVER BRIDGE
➡ PRESTRESSED CONCRETE BRIDGES
➡ REINFORCED CEMENT CONCRETE BRIDGES
→ R.C.C. SLAB BRIDGE
→ R.C.C.T-BEAM & SLAB BRIDGE
→ R.C.C. CONTINUOUS BRIDGES

9. → STEEL GIRDER BRIDGE
Girder bridges are the simplest
bridge type in structure and
consist of steel beams shaped to
an I-section or box section, called
a plate girder bridge or a box
girder bridge, respectively. Girder
bridges are comprised of deck
slabs, on which vehicles and
people pass, and of main girders
supporting the deck slabs.

10. → STEEL TRUSS BRIDGE
Truss bridges are formed with a
structure of connected elements
that form triangular structures to
make up the bridge. Trusses are
the triangles that connect to the
top and bottom cord and two end
posts. The trusses make up
reinforcement for the bridge that
even the load-bearing across the
structure.

11. → CONTINUOUS STEEL BRIDGE
When the track of Railways span
continuous , through type steel
truss supports the floor of bridge,
it is called continuous steel
bridge. The truss can be
supported by R.C.C. piers, this
bridge is economical in case of
material used and facilitates its
erection of more than one span
without false work.

12. → STEEL CANTILEVER BRIDGE
The steel truss cantilever bridge
was a major engineering
breakthrough when first put into
practice, as it can span distances
of over 1,500 feet (460 m), and
can be more easily constructed at
difficult crossings by virtue of
using little or no falsework.

13. ➡PRESTRESSED CONCRETE BRIDGES
In the field of bridge engineering,
the introduction of prestressed
concrete has aided the
construction of long-span
concrete bridges. These often
comprise precast units, lifted into
position and then tensioned
against the units already in place,
the process being continued until
the span is complete.

14. → R.C.C. SLAB BRIDGE
Solid Slab bridges are horizontal
beams supported at each end by
substructure units and can be
either simply supported when the
beams only connect across a
single span, or continuous when
the beams are connected across
two or more spans. When there
are multiple spans, the
intermediate supports are known
as piers.

15. → R.C.C. T-BEAM & SLAB BRIDGE
RCC T-BEAM BRIDGES • T-Beam
construction consists of a
transversely reinforced slab deck
which spans across to the
longitudinal support girders. T-
Beam bridges are economical for
spans 12m to 18m. Optimum
lateral spacing of longitudinal
girders is typically between 1.8 m
to 3m.

16. → R.C.C. CONTINUOUS BRIDGES
The bridges that have more than
one span of R.C.C. can be termed
as R.C.C. continuous bridges. They
have less expansion joints and
thus economical. But very little
settlement of foundation can lead
to failure, apart from this
property, they are suitable to
construct long spans.

17. Danger zone 3