CIE 2102:Mechanics Of Structure

Arches and suspension bridges

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Arches and suspension bridges

Rashma R S V

Three Hinged Arches

Arches are curved beams that transfer loads

Statically determinate

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components

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Arch subjected to loads

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Any section in arch is subjected to normal thrust, N, Radial Shear, Q and Bending Moment

Type 1 - Circular/segmental arches

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Type 2 - Parabolic arches

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Type 3 - Parabolic arches with

springing at different levels

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Steps for Analysis of Three Hinged Arches

1. Calculate end reactions

2. Find Horizontal reaction by applying

Moment about crown equals zero.

3. Find slope at the section and determine

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3. Find slope at the section and determine

normal thrust and radial shear

4. Find Bending Moment at the section

required.

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Suspension Bridges

The cable and girder are connected by

hangers/suspenders

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components

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FBD of Girder and cable

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FBD

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FBD of cable

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Steps for Analysis of suspension bridges

1. Draw the free body diagram of cable and

girder

2. Calculate end reactions considering external

loading

3. Determine equivalent udl taking moments

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3. Determine equivalent udl taking moments

about c=0

4. Find Horizontal reaction and vertical reaction

of cable

5. Calculate slope and maximum tension in the

cable15

The End

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The End