Design of Strap Footing

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Date :

Job No. :

Sheet : Cont'd

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Project : Subject :

Description :

Design of Strap Footing CALCULATION

Pa Ha

Note : Enter Da Data in Cells marked

Pb

only

S 9000

Ma  Aa (Soil level)

da

Strap Beam Ta x 250

e

75 mm (min) 5650

La / 2

1500

1250

Ra =

600

S'

3143

kn

7750

Rb =

Data

kn

Steel Strength

fy'

410

Mpa

b

1000

mm

Concrete Strength

fc'

30

Mpa

Soil Bearing Capacity

pbc

200

kn/m2

d cover 

1000 75

mm mm

d'

925

mm

Loading Data

kn

kn.m

kn

kn

Spacing between footings

Pa 2500.00

Ma

Ha

Pb

9.00

0.00

0.00

100.00

0.00

0.00

0.00

22.00

2500.00

0.00

0.00

Dead Load wind load

1.00

-136

Strap Beam Data

Total Footing Data -

A

S m

* N.B : Loads above are service.

234.80 Footing Data -

Side Beam and wall loads

B

beam

Soil level

Aa

0.00

m

Soil level

Ab

0.00

m

b

300

mm

Depth of soil

Da

1.00

m

Depth of soil

Db

1.00

m

d

500

mm

Col dist from edge Xa

0.250

m

L

8000

mm

Length of footing

La

3.00

m

Length of footing

Lb

1.20

m

wt

30.0

kn

Width of footing

Wa

3.20

m

Width of footing

Wb

1.20

m

wall

Eccentricity

Ea

1.25

m

L

8000

mm

1.00

m

Depth of footing

Tb

0.40

m

ht

3000

mm

240.00

kn

Ftg wt + soil wt

29.95

kn

3.45

kn/m

82.80

kn

Depth of footing

Ta

Ftg wt + soil wt Bp

0.50

m

Brdth of pedestal

Bp

0.40

m

wt / lin mt / lin ht

Depth of pedestal Dp

0.50

m

Depth of pedestal Dp

0.40

m

wt

Wt of pedestal

0.00

kn

Wt of pedestal

2.40

kn

others

237.20

kn

 wt

0

kn

total wt others

112.80

kn

Brdth of pedestal

Wp

Total axial load Ra

Pa

2500.00

3143.23

kn

5.24

m

Wa(Reqd)

kn

Total axial load Rb

not ok

Wp Pb

-136.07

kn

-0.57

m

Wb(Reqd)

ok

pbca'

327.42

kn/m2

pbcb'

-94.50

kn/m2

pbca' / m

1047.74

kn/m

pbcb' / m

-113.39

kn/m

Shear(kn) & Moment(kn.m) Calculation V1 V2

241.94 -2258.06

M1 M2

-2520.16

B D Mu (mm) (mm) Kn.m

r (%)

As rq (mm2)

Reinforcement (top)

-241.94

1000 1000 4156

1.60

14793

19

-20.41

Vu

30.24

V3 V4

403.23

V5 V6

335.19

Mmax

(Kn) (Kn)

68.04

-2597

645

403.23

M3 M4

Design of Strap Beam

Vc 844

stirrups �

10

 /

184

�

Reinforcement (bottom)

� 32 18 16  steel ratio > min. o.k.

spacing < ( d/2 ) o.k.

Prep by : Ahmad Basha Quadri - Abq Consultants - 12-2-826/2 Royal residency, flat no 503, besides Amba Theatre, Mehdipatnam, Hyderabad 500028, A.P India, - www.abqconsultant www.abqconsultants.com s.com -9959010210

Prepared by :

Date :

Job No. :

Sheet : Cont'd

Verified by :

Date :

Revision Notes :

Project : Subject :

Description : CALCULATION

DESIGN OF EXTERNAL FOOTING qu

Mu

Kn/m2 Kn.m

327

DESIGN OF INTERNAL FOOTING

r

As rq

Reinf. Per Meter

As pr

qu

Mu

r

As rq

(%)

(mm2)

(each way)

(mm2)

Kn/m2

Kn.m

(%)

(mm2)

(each way)

(mm2)

-94.5 -12.1

0.18

585

12 12 @ c/c 193

679

477 0.18 1665

20 1885 20 @ c/c 189 �

6

Reinf. Per Meter 6

�

As pr  

Shear & Moment Diagram 2500

Kn

237

Kn

-94

Kn/m2

Weightless

327

Kn/m2

NOT OK - SBC > Than allowable

V1

241.9

NOT OK -

Footing going in uplift - increase SIZE, SW or DL

403.2

V3

V5

335.2

V6

68.0

M4

-20.4

V4

403.2

Shear Diagram - kn V2

-2258.1

xcg =

2.333

m

30.2

M1

M2

-2520.2

M3 Mm

-241.9

-1381.0

Mmax = -2597.2

kn.m

Moment Diagram-kn.m SUMMARY DESIGN OF FOOTING

LOCATION

L

B

T

SHORT REINF.

LONG REINF.

m

m

m

EXTERNAL

3

3.2

1

12

�

25

20

�

20

INTERNAL

1.20

1.20

0.4

9

�

12

9

�

12

B

D

BOTTOM

mm

mm

REMARKS

SUMMARY DESIGN OF STRAP BEAM

1000 1000

TOP

STIRRUPS

REMARKS

REINFOCEMENT REINFOCEMENT 18

�

16

19

�

32

�

10

/

184

spacing < ( d/2 ) o.k.

Prep by : Ahmad Basha Quadri - Abq Consultants - 12-2-826/2 Royal residency, flat no 503, besides Amba Theatre, Mehdipatnam, Hyderabad 500028, A.P India, - www.abqconsultants.com -9959010210

Prepared by :

Date :

Job No. :

Sheet : Cont'd

Verified by :

Date :

Revision Notes :

Project : Subject :

Description : CALCULATION

19

�

32

@ top

7

�

32

rest

 A

2880

 A stirrups �

10

/

11

�

20

For reinforcement

@ bottom

and stirrups refer

184

Beam details.

   0    0    0    1   =    d

DETAILS OF STRAP BEAM

b =1000 SECT A-A

Strap Beam

1000

400 75 mm (min)

500

20

�

20

12

�

Strap Beam

   0    0    5

�

�

12

400

12

25 9

   0    0    2    3

9

   0    0    0    1

   0    0    4

   0    0    2    1

NOT OK. Width of Pedestal should be >= Width of Strap Beam 250

2750 3000

PLAN

1200 Internal Footing Fb

External footing Fa

Prep by : Ahmad Basha Quadri - Abq Consultants - 12-2-826/2 Royal residency, flat no 503, besides Amba Theatre, Mehdipatnam, Hyderabad 500028, A.P India, - www.abqconsultants.com -9959010210