Foundation Design using SAFE

1)

AIM:

• To analyse and design isolated footing from week11 on SAFE
• To verify the size, depth and steel provided as per the calculations

PROCEDURE:

• Open SAFE application
• 
• Select new model
• 
• Input setting -----> Unit is to be slected as Mertic and code as IS456-2000.
• 
• Select SINGLE FOOTING
• Subgrade modulus = F.O.S X S.B.C = 3 X 150 = 9000 KN/cu.m
• The compression axial load for load calculation is (1.5 D.L + 1.5 L.L) is 2000 KN/cu.m
• Unfactored load = (2000/1.5) = 1333.3 KN
• Therefore, (1333.3/2) = 666.5 KN
• Footing thickness =800 mm
• 
• Define material
• 
• Add new material property
• Add M25 grade of concrete
• 
• Material property data
• 
• Material property design data
• 
• Add rebar fe500
• 
• Add new material property
• Material property data
• 
• Material property design data
• 

• Material property data :

  Click on define material properties

  M25 grade of concrete

  Modulus of elasticilty (E) = 25000N/sq.mm

• Define slab properties
• 
• Define footing properties
• 
• Define propertie for mat
• 
• Define properties for stiff
• 
• Define load pattern
• 
• Define soil subgrade modulus
• 
• 
• 
• Assign point load
• 
• 
• Assign load combination
• 
• Check deisgn prefrence (minimum cover 50 mm)
• Run and anaysis design
• 
• 

Result :-

Hence, isolated footing is designed and run successfully on SAFE.

2)

AIM:

• To model, analyse and seign the pile cap on SAFE
• To evluate the following

1. Pile group to be used
2. Depth of pile cap
3. Longitudinal steel on top and bottom face in both directions

Given data:

• Column of size 600x600
• Unfactored gravity load (DL+LL) of 1175 KN
• Piles of 16 metres length
• Piles of 500 mm diameter
• Load carrying capacity of 200 KN

Calculations

• No.of piller = (1175/200) = 5.8 =6nos
• Spring constant = `(E xx A) / L`

where, E = 25000N/sq.mm

Area (A) = `(pi /4 ) X 500^2`

= 196349 sq.mm

Pile length = (L) = 16000mm

Spring constant = `(E xx A)/L` = `(26000 xx 196349)/16000` = 306795 N/sq.mm

Edge spacing is taken as 200 or 300mm.

PROCEDURE:

• Open SAFE application
• Slect new model
• Followed by input settings
• Select units as metric and code as IS456-2000
• 50mm top and bottom cover is provided.
• 
• Cordinate wad define
• Grid spacing in X and Y direction was taken as 2.9m and 1.65m
• Shown below
• 
• 
• Define material property
• Material property data :
• Click on define material properties
• M25 grade of concrete
• Modulus of elasticilty (E) = 25000N/sq.mm
• 
• Fe500 rebar are added as shwn below
• 
• Define slab properties
• Define pile cap
• 
• Define column
• 
• Define pile details
• 
• Draw slab by using quick draw tool
• 
• Draw points
• 
• Add piles at point
• Modify edge distance 0.3m
• 
• Create column of 600X600m
• Draw column in center using quick draw tool
• 
• Spring were added
• Select pile ----> assign ----> support data ----> spring point
• Spring constant is taken from above calculation
• 
• D.L and L.L are taken as 587.5KN
• 
• define load combination design
• 
• 
• Run analysis
• maximum displacement was found to be 0.84
• Thus, safe
• 
• All punching shear value are less than 1.....Thus, safe
• 
• Joint reaction, rections are in limits.....Thus, safe
• 
• Reinforcement detais in X and Y direction and run the analysis again
• 
• Reinforcement slab design
• 
• 
• Pile cap foundation design
• 

RESULT :

The designed result of given pile cap foundation is shown below