Foundation Design using SAFE
Aim
1. Model the isolated footing provided in week 11 challenge on SAFE.
For Que 1.
Procedure
Open the SAFE software
Start with the new model.
Select the design preferences as metric unit and IS 456.
Select the cover as 50 mm.
Calculation
Select the single footing & the dead load and live load.
Calculation of modulus of elasticity.
Now define the material as shown in the below image path.
Defining the M 25 material.
Now defining the rebar material as Fe 500.
Now defining the slab property as Mat.
Defining the slab property as stiff for column placement.
Now defining the slab property as footing and slab material M25.
Now define the soil property from the below given path.
Putting the value of subgrade modulus as we have calculated above.
Changing the rebar material of footing as Fe 500.
Assigning the soil property to Mat or Footing.
Assigning the point load to the column as given in the question.
Applying the dead load.
Assigning the load combination data.
For SLS & ULS
Now drawing the design strip.
This footing is safe in punching.
As shown in the below image.
Longitudinal reinforcement at top and bottom.
Result
- This putting design is safe in all criteria.
For Que 2.
Aim
2. Model, analyse and design the pile cap on SAFE to evaluate the following:
- Pile group to be used
- Depth of pile cap
- Longitudinal steel on top and bottom face in both directions
Procedure
Open the SAFE software
Start with the new model.
Select the design preferences as metric unit and IS 456.
Calculation
we can take the edge spacing as 250mm.
Grid setting.
Defining the slab property as above question.
Assigning the pile cap.
Drawing the point where we have to put the pile.
Placing of the pile & end column of 600 x 600mm.
Defining the spring property data for the pile base.
Assigning the dead load as given in the question.
Assigning the spring constant to the base of pile.
Defining the load combination for Ultimate and Serviceable limit state.
Draw the Column design strips.
Maximum deformed shape under Dead load condition, After analysis and design.
Below image shows the punching shear value.
The punching shear value is < 1.
Here, Base reaction value is shown in the figure.
But the Question has mention that the pile capacity is 200 KN for each.
So, it doesn't satisfied the condition.
So it neeed to be modefied
So we have made the changes in the thickness of the Pile cap from 800mm to 700mm.
Modefied result
For base reaction
Longitudinal reinforcement
Result
- The foundation design with pile is safe inn all criteria mention in assignment.