Challenge

Week 1 Challenge

SSmarak Priyaranjan26 Feb 2023

Bridges

AIM OF THE EXPERIMENT:-

To Calculate the Dead Load of the Box Girder given in the above figure and apply it in Staad Pro. and perform analysis.

SOFTWARE REQUIRED:-

Staad Pro.

THEORY:-

Deadload:-

A constant load in a structure (such as a bridge or building) that is due to the weight of the members, the supported structure, and permanent attachments or accessories.

Components of Bridges:-

Sub-structure
Super-structure

Sub-structure:-

Pile/Well Foundation
Pile Cap/Well Cap
Pier
Abutment
Wing Walls
Pier Cap
Pedestal
Bearing

Super-structure:-

Girder
Deck Slab
Truss
Parapet

MATHEMATICAL CALCULATION:-

Data Given:-

Width of the Bridge Deck=10.2m or 10200mm

Span of the Bridge=12m or 12000mm

Pier Size=2.5m dia.

Seismic Zone=IV

Wind Speed=47kmph

Unit Weight of soil=19KN/m^3

CALCULATING "A"

According to the Figure,

Since, width of the bridge deck=10.2m or 10200mm

We have the Centre Line, so the Bridge deck is divided into two equal parts

Hence, Width=10200/2=5100mm

Now "A"=5100-4200=900mm

DEADLOAD CALCULATION:-

Since it is a box girder with inclined angle, we have to divide the whole structure into number of rectangles and triangles

Sl.No	Type of Figure	Length/Base(m)	Thickness/Height(m)	Area(m^2)	Weight(KN/m) AreaDensity of Conc. i.e. (Area25)
1	Rectangle	10.2	0.225	2.295	57.375
2.	Rectangle	4.02	0.200	0.804	20.1
3.	Rectangle	2.115	0.250	0.528	13.21
4.	Rectangle	2.115	0.250	0.528	13.21
5.	Triangle	1.2	0.125	0.075	1.875
6.	Triangle	1.2	0.125	0.075	1.875
7.	Triangle	1.370	0.125	0.085	2.14
8.	Triangle	1.370	0.125	0.085	2.14

Hence, The total was found out to be=111.925KN/m

STAAD PRO. METHODOLOGY

Staad Pro. V8i Software was opened.
A new Folder was created on PC.
On Staad Pro. Check on New Project
Set Unit and Force Unit as Metre and Kilo Newton.
Check on Space
Mention the Project Name and the Project Location

Click on Next
Check on Add Beam

PROCEDURE:-

Let us Assume, the height of Pier=10m
The entire structure will be modelled as SLD(SINGLE LINE DIAGRAM)
In Geometry, The model was prepared as per the requirement

For, Creating Dummy Beam,i.e. the density of material will be "0"

Go to General----------Material-------------Create-------------Density=0

Property Assign

FOR PIERS

Go to General,
Select Property,
Select Define,
Select Circle,
Mention Yd value=2.5m (Data Given)

FOR BOX GIRDER

Go to General,
Select Property,
Select Define,
Select Rectangle,
Mention Yd and Zd value=0.1m respectively
also assign the dummy material to the girder element

SUPPORT CONDITION:-

Go to General
Click on Support
Click on Create
click on Fixed and then Ok
Click on the support that you have prepared and assign it on the respective base.

APPLICATION OF LOADINGS:-

Go to General
Click on Loads and Defination
Select on Load Case Details
Click Add
Select Loading Type as Dead
In Title, Type DL
Then Add

Click on Load Case 1 "DL"
click on Add
Select self weight
Click on Add
Click on Member load, click on Uniform Force and give the Force value -111.925KN/m (-ve value because force is acting in downward direction)
Then Close