Week 10 Challenge

Aim : Calculate the Snow Load for the proposed bridge using IS 875 part IV and Analysis using STAAD PRO 

Introduction : 

In this Challenge  I have to calculate the snow load using given data.
The span of bridge is 10m
Total width of Bridge is 18m 

Calculation :

setteled snow load Weight = 200 - 300 kg/m3
Depth of snow = 1.25m 
flat deck B < 30degree>

Snow load :  Density of snow x depth x span 

                            = 3 x 1.25 x 10 

                            = 37.5 kn/m

shape coefficient from IS 875 part IV 

                                   u = 0.8

                     Design snow load = 0.8 x 37.5 = 30kn/m 

ASSUMPTIONS :

Height of pier = 5m 
dia of pier = 1.5m 
Girder size = 0.75m x 1.5m
Plate thickmess = 0.9m

       thickness of parapet wall= 0.050m     

STAAD PRO WORK :

MODEL CREATION :
Create a node at 0,0 and the copy it at 5m below , add a beam between this two node as a column 
select the beam and copy it in Z direction as a 3 steps we will get total 4no of piers 
Select this 4pier and copy it in x direction at a distance of 10 m to get a span 

Now we have to add a beam between those piers as amain girders and cross girders

Now we created all beam structure on staadpro 
For deck slab we have to create a plate on top as a deckslab 
Select the corner node and copy it in z direction and select that both and copy at x direction 
add a plate between those 4 nodes and copy the plate on whole structure 

Now i have to create a cantilever span of bridge and assign parapet wall on both sides
Select the corner line of plates and copy it in z direction 
Create a vertical plate for the parapet wall 

Our Staad pro model is ready .

Assign the fixed supports at a lower nodes of pier 

      2. PROPERTIES 

After succesfully model making we have to give properties to the all the components of bridge 
Click on properties and define the properties 
for pier : Cir , concrete 1.5m diameter 
for girder : rectangle , concrete 0.75m x  1.5m 
for deck slab : Plate thickness of 0.9m 
For parapet wall : plate thickness 0.050m 

Now we successfully applied all the properties to the components 

      3. LOAD APPLICATION 

As per the load we calculated we have to apply load on deck slab 
Click on load Create a load case name as Snow load 

Click on load case add a Plate load as we calculated abobe 30kn/m
After adding load select the all plates of deck and assign the load to the deck slab 
we have to apply load in Global Y direction 

     4. ANALYSIS 

Click on Analysis and design add a command of perform analysis 
Click on Run Analysis 

     5.RESULTS :