pile foundation of burj khalifa

foundation details of burj khalifa

1. Sir M Visvesvaraya Institute of Technology 2017-2018 Department of Civil Engineering

2. Presented by Sunil prasad 1mv14cv056 Seminar on

3. Content Introduction PILE APPLICATION s TYPES OF PILES PILE CAPCITY CASE STUDY OF BURJ KHALIFA cathodic protection Geotechnic a l I n vestigation Reference

4. WHAT IS PILE FOUNDATION It is that type of deep foundation in which the bed are taken to a low level by mean of vertical members which may be timber, concrete or steel Pile ???? A sl e n d e r , s tru c tural member c o n si s ting ste e l or concrete or timber. It is installed in the ground to transfer the structural loads to soils at some significant depth below the base of the structure.

5. Where it is adopted …? Piles are adopted when the loose soil extended to a great depth. The load coming from the structure is very high & the distribution of the load on soil is uneven. The subsoil water level is likely to rise or fall appreciably. The pumping of subsoil water is too costly for keeping the foundation trench in dry condition. The structure is situated on sea shore or river bed and the foundation is likely to adopted by the scouring action of water.

6. Soft to Firm Clay Large Distributed Weight Very Large Concentrated W eig h t Strong Rock Low W eig h t Pile applications

7. Transmit most of their load through the layers through which the piles pass, i.e., mostly through the surface friction with the surrounding soils. Types of pile FRICTION PILES Q b >> Q s ( )

8. Transmit most of their loads to the load bearing layer (dense sand or rock). Most of the pile capacity inferred from the end bearing point. Bearing piles ( Q b >> Q s )

9. Pile foundation is the combination of skin friction &end bearing

10. Based on installation Displacement piles Non displacement piles DURING THE INSTALLATION OF PILE ,A LARGE AMOUNT OF VOLUME OF SOIL IS DISPLACED LATERALLY & UPWARDS exa mple driven piles soil is removed and the resulting hole filled with concrete or a precast concrete  pile  is dropped Into the hole and grouted in. example bored piles

11. Q s = fA s f = Unit Frictional resistance A S = Shaft Area (Pile surface area ) q b = Unit Bearing Capacity A b = Area of Pile Base Bearing capacity of piles from soil parameters: Static Formula Method ( Q u = Q b + Q s ) Pile capacity o Theoretical Approach :- In this approach the pile capacity is calculated using some formula in which the soil data is fed for obtaining the capacity . Q u = Ultimate Bearing Capacity Q b = q b A b Embedded = D

12. Reinforced concrete raft that is 3.7 meter thick and made of High Performance Self Compacting Concrete Cathodic Protection System that creates a barrier to keep “eroding chemicals” from ground water affecting the concrete Low permeability and high density = greater protection from ground water 192 piles that are 47 meters in length. 1.5 meters in diameter (piles) and placed 3.75 meters apart from center-to-center Case study of burj khalifa foundation

13. cathodic protection ???? Cathodic protection is a technique used to control the corrosion of a metal surface by making it the cathode of an electrochemical cell. Zinc,aluminium,magnesium Are more electronegative Than steel so they can be used as sacrificial anodes

14. Placement of anode on a reinforcement bar cage

15. Geotechnic a l I n vestigation a nd Testing Program Moisure content Aterberg limit Specific gravity Particle size distribution Direct shear test Unconfined compressive strength

16. Geotechnic a l I n vestigation a nd Testing Program Standard Penetration Test (SPT) Pressuremeter Tests Drilling of geophysical boreholes Installation of standpipe Piezometers

17. Pile Load Testing Static load tests on seven trial piles prior to foundation construction. Static load tests on eight works piles, carried out during the foundation construction phase (i.e. On about 1% of the total number of piles constructed). In addition, dynamic pile testing was carried out on 10 of the works piles for the tower and 31 piles for the podium, i.e. On about 5% of the total works piles.

18. TEST SCHEMATIC DIAGRAM FIELDSET UP

19. The soil stratum of Dubai is very week so they had to excavate up to 50m deep to get a hard rock structur e But the rock that they found was fragile and saturated with ground water So that any hole made will be cured immediately EXCAVATION

20. EXCAVATION Cont. The engineers filled this with a viscous polymer slurry This pushes the rock and the ground water to the e dges of the boreholes to keep it open This slurry is denser than water and ligher than concrete, so that when concrete is pumped the concrete displaces the fluid and forms the foundation.

21. Pictorial Description

22. High performance concrete(HPC ) Low permeability High durability M80-M60 cube strength concrete was used It includes fly ash, Portland cement,Silica fume Two largest concrete pumping machines in the world were used for this purpose For reducing cracks due to high temperature concreting was done only at night Concrete used

23. Plan of the Foundation

24. Actual Photograph of the Foundation

25. IS 2911 : Part 1 : Sec 1 : 1979 Driven cast in-situ concrete piles IS 2911 : Part 1 : Sec 2 : 1979 Bored cast-in-situ piles IS 2911 : Part 1 : Sec 3 : 1979 Driven precast concrete piles IS 2911 : Part 1 : Sec 4 : 1984 Bored precast concrete piles IS 2911 : Part 2 : 1980 Timber piles IS 2911 : Part 3 : 1980 Under reamed piles IS 2911 : Part 4 : 1985 Load test on piles IS 5121 : 1969 Safety code for piling and other deep foundations IS 6426 : 1972 Specification for pile driving hammer IS 6427 : 1972 Glossary of Terms Relating to Pile Driving Equipment IS 6428 : 1972 Specification for pile frame IS 9716 : 1981 Guide for lateral dynamic load test on piles IS 14362 : 1996 Pile boring equipment – General requirements IS 14593 : 1998 Bored cast-in-situ piles founded on rocks – Guidelines IS 14893 : 2001 Non-Destructive Integrity Testing of Piles (NDT)

26. REFERENCES NPTEL (National Programme on Technology Enhanced Learning) http://archrecord.construction.com Poulos, H.G. (1988). “Cyclic Stability Diagram for Axially Loaded Piles”. Jnl . Geot . Eng., ASCE, Vol. 114 (8): 877-895 http://www.archinomy.com www.burjkhalifa.ae

27. Thank you