1. Pertemuan 05 Daya Dukung Tanah
Matakuliah : S2094 / Rekayasa Pondasi
Tahun : 2005
Versi : 1.1
Pertemuan 05 Daya Dukung Tanah

2. Shallow Foundations Bearing Capacity
The problems of soil mechanics can be divided into two principal groups - stability problems and elasticity problems
- Karl Terzaghi, 1943

3. Karl Terzaghi (1883-1963) Father of modern soil mechanics
Born in Prague, Czechoslovakia
Wrote “Erdbaumechanick” in 1925
Taught at MIT ( )
Taught at Harvard (1938 and after)

4. Karl Terzaghi at Harvard, 1940

5. Bearing Capacity Failure; Fargo Grain Elevator, N. Dakota

6. Transcosna Grain Elevator, Canada Oct. 18, 1913
West side of foundation sank 24-ft

7. Stability Problem Bearing Capacity Failure
Bearing Capacity Analysis
How do we estimate the maximum bearing pressure that the soil can withstand before failure occurs?

8. Bearing Capacity Failures
Types/Modes of Failure
general shear failure
local shear failure
punching shear failure

9. General Shear Failure

10. Punching Shear Failure

11. Model Tests by Vesic (1973)

12. General Guidelines Footings in clays - general shear
Footings in Dense sands ( > 67%)
-general shear
Footings in Loose to Medium dense
(30%< < 67%) - Local Shear
Footings in Very Loose Sand ( < 30%) punching shear

13. Bearing Capacity Formulas

14. Terzaghi Bearing Capacity Formulas

15. Terzaghi Bearing Capacity Formulas
For Continuous foundations:
For Square foundations:
For Circular foundations:

16. Bearing Capacity Factors

17. Terzaghi Bearing Capacity Formulas
D  B
No sliding between footing and soil
soil: a homogeneous semi-infinite mass
general shear failure
footing is very rigid compared to soil