Foundation Design using SAFE

AIM : Model the isolated footing provided in week 11 challenge on SAFE. Analyze and design it to verify the size, depth and steel provided as per calculations.

INTRODUCTION :

• Isolated footing are the type of footing that can transfer load from the single column to the ground soil beneth it
• They are slopped isolated footing and stepped isolated footing

PROCEDURE :

• Open the safe model and create the model grid of the week 11 challange
• Click on edit grid to specify the grid distance in X and Y direction

• Specify the grid distance as per week challange 11

• First define material property for the footing and the column click on define , material and add new material

• E = 5000 under root Fck = 5000 X root 25 = 25000
• Desity of concrete 25 kN
• Cube strength for 28 days 25 N/mm^2

• Same for the rebar property

• For the footing type depth is 500 mm

• PICK QUCIK DRAW AROUND POINT

• Add column size as 0.5 X 0.5 m

• select the footing property and assign soil property to the footing and SBC of soil is 150 N/mm^2

• Assign dead load and live load to the footing and column or stiff

• Load combination of Ultimate load combine dead load and live load

• Load combination for SLS combination of Dead load and Live load

• Design preferences check for cover

AIM : . A column of size 600x600 carrying an unfactored gravity load (DL+LL) of 1175 KN is to be supported on pile cap, which ultimately transfers load to the piles underneath. Piles of 16 metres length and 500 mm diameter are to be used. Each pile has a load carrying capacity of 200 KN. Model, analyse and design the pile cap on SAFE to evaluate the following:

Introduction :

• Pile foundation is used where the soil strata is loose and SBC of soil is low
• The column can not able to transfer the load to the soil
• Piles are commonly used in place where the clay soil is presence
• Pile are used in deep foundation

Procedure :

Given Dead load + Live load = 1175

Each pile capacity of 200 KN

Number of pile = Axial load / Pile capacity

= 1175 / 200

=5.8 = 6 piles

Taking least value in soil test for SBC

Spring constant = EA/L

E = 5000 under root Fck Taking Fck value as 30 = 27386 N/mm^2

A = pi X d^2/4 mm ^2

L = 16 mts

Spring constant = 336.05 KN/mm^2

Spacing between pile = 2.5 times of dia of pile

= 2.5 X 500 mm

= 1250 mm between spacing of pile

• Grid spacing in X and Y direction

Draw pile cap by pick draw rectangle slab area

Point distance is 0.450 (distance of edge + radius of pile ) 200 + 250

Draw , draw point specify the distance

For column point distance 0.625

Go to assign support Data point spring value in Z direction

Assign load for column of 1175 KN