PT STRUCTURES IN BUILDINGS

1. 09/09/2014 – GBB – Le béton post-contraint Practical applications of post-tensioned concrete in buildings François LEPERS CEO of GAMACO Ingénieurs-Conseils

2. Practical applications of post-tensioned concrete in buildings I. PT slabs I. Flat PT slabs II. Flat PT slabs with drop panels III. Slabs with PT beams IV. Waffle PT slabs V. Lightened PT slabs VI. PT slabs on wide slabs VII. PT Foundation rafts II. PT transfer structures I. PT transfer beams II. PT transfer slabs III. Special PT applications I. Wall prestressing II. Hangers III. External reinforcement of existing structures IV. Post-tensioned concrete in silo’s

3. Post-tensioned slabs (PT slabs) (1) 2 effects of the post-tensioning on the structures: • Compression force • Balanced loads Global impact on the building design: • reduced structure height • No beams needed Sketches from commercial documentation Freyssinet PT slabs can be used in all kind of buildings : office buildings , apartment's building, hospital, commercial center's, parking's, sport infrastructures, …

4. Post-tensioned slabs (PT slabs) (2) Specific design consideration regarding to PT structures Sketches from PT-structures.com The slab has to be able to shorten freely at jacking (elastic shortening due to the compressive forces) When unfavorable cases occurs, specific execution details can be adopted to maximize the compression force in the slab.

5. Post-tensioned slabs (PT slabs) (3) Execution design studies : usually in charge of specialized sub-contractors, as it is also the practice in the industry for precast elements

7. Flat PT slabs (1) bi-directional behavior – no beams Classical Span/depth ratio : (Hyperstatic slabs) Overloads Span/Depth 1.5 kPa Up to L/45 2.5 kPa Up to L/40 5.0 kPa Up to L/35 Admissible spans : usually 6 to 12 m, but 16m often used in parking structures Typical passive reinforcement : general bottom mesh, top bars over the columns only, punching shear reinforcement and bursting/edge reinforcement

8. Flat PT slabs (3) 110 000 m² of flat PT slabs: AZ GROENINGE - KORTRIJK 30000m² in 2004 (Cordeel) 75000m² in 2013 (CEI De Meyer & Jan De Nul) Flat slab 250mm Typical grid : 8.1m x 8.1m Typical overloads : 6.0 kPa Unbonded & bonded system 75000m² = 7 months on site ! +- 600m²/week/crane (5 cranes)

9. Flat PT slabs (4) EUROMED CENTER II – MARSEILLE - FRANCE 45 000 m² of flat PT slabs Mixed building : parking, hotel, gardens, shopping mall & offices Spans from 6.0m to 8.5m

10. Flat PT slabs (5) DOCKS DE LYON – LYON - FRANCE 3 000 m² of flat PT slabs (currently in progress) 6 levels of offices Spans : max 8.5m Cantilevers : max 3.5m Slab depth : 300mm, including integrated heating/cooling system (active floor)

11. Flat PT slabs (6) BANK ACCORD – CROIX - FRANCE 8 000 m² of flat PT slabs (2013) - parking (2.5 kPa) - offices (6.0 kPa) Spans : 10.m x 8.5 m Slab depth : 250 / 260mm

12. Flat PT slabs (7) MAISON DES SCIENCES HUMAINES – BELVAL - LUXEMBURG 30 000m² of flat PT slabs (2011-2012) Spans : 12.0m isostatic & 12.0m x 8.0 m Overloads : 6.1 kPa Slab depth : 360 mm Main engineer : BEST 12m 12m 8m

13. Flat PT slabs (7) ARENDT HOUSE – KIRCHBERG - LUXEMBURG 8000m² of flat PT slabs (2013) Spans : Maximum 17.0m Overloads: 6.0 kPa Slab depth : 35 cm Main engineer : INCA 17m

14. Flat PT slabs (8) GHELAMCO ARENA - GENT 10000m² of flat PT slabs (2013) Spans : 10m x 10 m Overloads : 5.0 kPa Slab depth : 300 mm

15. Flat PT slabs (9) PUBLIC PARKING – LA GARDE - FRANCE 12500m² of flat PT slabs (2012) 2 levels of parking 1 roof level with high loadings Spans : 16.0m x 6.0 m Overloads : Parking 2.5 kPa Roof 22.0 kPa Slab depth : Parking 350 mm Roof 550 mm

16. Flat PT slabs (10) PUBLIC PARKING – BETHUNE - FRANCE 10000m² of flat PT slabs 2 levels of parking 1 roof level with high loadings Spans : 16.0m x 6.0 m Overloads : Parking 2.5 kPa Roof 25 to 30 kPa Slab depth : Parking 350 mm Roof 550 mm

17. Flat PT slabs (11) PUBLIC PARKING – BETHUNE - FRANCE

19. Flat PT slabs with drop panels (1) bi-directional behavior – no beams Classical Span/depth ratio : (Hyperstatic slabs) Overloads Span/Depth 2.5 kPa Up to L/45 5.0 kPa Up to L/40 Admissible spans : from 10 to 16m

20. Flat PT slabs with drop panels (2) COMMERCIAL CENTER IKEA – MOSCOW - RUSSIA 15 000m² of flat PT slabs Project of commercial center Spans : 16.0m x 16.0 m Overloads : 15 kPa Slab depth : 400mm + capital 4000x4000x300mm

22. slabs with PT beams (1) one-directional behavior Classical Span/depth ratio : (Hyperstatic slabs) Overloads PT Slab Span/Depth Beams Span/Depth 2.5 kPa Up to L/45 Up to L/25 5.0 kPa Up to L/40 Up to L/20 Typical example : grid 16.0m x 8.0m bi-directional behavior Classical Span/depth ratio : (Hyperstatic slabs) Overloads Slab Span/Depth Beams Span/Depth 2.5 kPa Up to L/45 Up to L/30 5.0 kPa Up to L/40 Up to L/25 Typical example : square grids from 12.0m to 20.0 m

23. Slabs with PT beams (2) PARKING & COMMERCIAL CENTER LECLERC – ROQUES (TOULOUSE) - FRANCE 35 000 m² Spans : 16.0m x 8.0 m Overloads : 2.5 kPa Slab depth : 200 mm Beams : 1000x600mm

24. Slabs with PT beams (3) PARKING OF THE AIRPORT – ISTANBUL - TURKIE 35 000 m² Spans : 16.0m x 16.0 m Overloads : 5.0 kPa Slab depth : 30cm Flat beams : 300x60cm

26. Waffle PT slabs (1) bi-directional behavior Classical Span/depth ratio : (Hyperstatic slabs) Admissible spans : up to 16m Overloads Span/Depth 2.5 kPa Up to L/30 5.0 kPa Up to L/25

27. Waffle PT slabs (2) Parking 28 000 m² Grid 16.0m x 7.0m Waffle slab 400mm PARKING OF A COMMERCIAL CENTER - AIX-EN-PROVENCE - FRANCE

28. Waffle PT slabs (2) Ovoïdal shape in plan view Waffle slab with variable thickness ERNST&YOUNG - KIRCHBERG - LUXEMBURG

30. Lightened PT slabs (1) Basic solution : polystyrene blocs (IMEC tower) Other solutions : Cobiax, Uboot, Bubbledeck, … The self-weight reduction is typically about 20% to 30% with this kind of solution. This allows to reduce the PT and RC ratios in the slabs. The economical balance has to be checked between material earnings and weight-reducing element costs.

31. Lightened PT slabs (2) PARKING ARLEQUIN – GRENOBLE - FRANCE 11 000 m² of lightened slabs (2013) Isostatic spans : 10.5 m Overloads : 2.5 kPa Slab depth : variable from 30 to 35 cm Lightening elements : Uboot

32. Lightened PT slabs (3) TWARDA TOWER – WARSAW - POLAND 25 000 m² of lightened slabs (2012) High-rise building – 44 floors max spans : 9.20m Slab thickness : 230 mm + Cobiax SL 120 Overloads : 5.0 kPa

34. PT slabs on wide slabs (1) MAISON DU SAVOIR – BELVAL - LUXEMBURG Cable profile Typical section

35. PT slabs on wide slabs (2) MAISON DU SAVOIR – BELVAL - LUXEMBURG

36. PT slabs on wide slabs (2) BRUSSELS AIRPORT - ZAVENTEM Terminal & Pier B 150 000 m² Grid 8.0m x 8.0m

38. PT Foundation rafts (1) WATER TREATMENT PLANT OF BRUSSELS NORTH - BRUSSELS Foundation raft on piles : 25 000 m² Other PT slabs : 50 000m² General contractor : Jan De Nul Piled raft supporting 10m of water

39. PT Foundation rafts (2) HALA CZYZYNY - POLAND Sport hall (Hockey) Foundation raft : 12 500m² Spans : up to 12m Thickness : 1000mm

41. PT transfer structures (1) Particularities : • Initial stage is often critical (reversed moment conditions) • Staging of the construction / jacking sequences Finitial = 0 High tensile stresses + cracks Finitial Finitial = = 0 100% 100% PT force 50% PT force 40% 100%

43. PT transfer beams (1) 8 isostatic beams 32 m AUDITORIUM - BORDEAUX Superior building with 4 concrete level to support over a spectacle hall Beams 200 x 220 cm

44. PT transfer beams (2) HOTEL DE REGION – TOULOUSE - FRANCE PT truss beam PT in the tie elements of the truss Cantilever 6.0m

46. PT transfer slabs (2) APPARTMENT BUILDING - TEMSE PT transfer slabs 240 mm

47. PT transfer slabs (2) Bi-directional flat slab CITE JUDICIAIRE - LUXEMBURG Max spans : 17.0m Slab thickness : 130 cm Loadings : 6 levels height building

50. Wall post tensioning (1) 2 cantilevers : 25m each MAISON DU SAVOIR – BELVAL - LUXEMBURG 1 central span > 50m Main engineer : Jan Van Aelst

51. Wall post tensioning (2) MAISON DU SAVOIR – BELVAL - LUXEMBURG 2 facade walls 2 inner walls

52. Wall post tensioning (3) MAISON DU SAVOIR – BELVAL - LUXEMBURG Inner walls Central span 50 m Tower basement Right cantilever 25 m Dilatation joint

53. Wall post tensioning (4) MAISON DU SAVOIR – BELVAL - LUXEMBURG Inner walls

54. Wall post tensioning (5) MAISON DU SAVOIR – BELVAL - LUXEMBURG Facade walls Central span 50 m Tower basement Right cantilever 25 m Dilatation joint

56. Hangers High-rise building (160m) TWARDA TOWER – WARSAW - POLAND 44 levels Cantilever 11m PT Hangers

58. External PT reinforcement of existing structures (1) EXHIBITION HALLS - CHARLEROI Legend: Main beams Carbon fiber reinforcement of the main beams External PT reinforcement of the secondary beams

59. External PT reinforcement of existing structures (2) Vertical component of the equivalent loads due to PT EXHIBITION HALLS - CHARLEROI

60. External PT reinforcement of existing structures (3) EXHIBITION HALLS - CHARLEROI

61. External PT reinforcement of existing structures (4) Particular anchor system have been developed for reinforcement of existing structures

63. PT concrete in silo’s (4) Annular compression = reduced cracks WATER TREATMENT PLANT – BEAURADE - FRANCE

64. Practical applications of post-tensioned concrete in buildings Thank you for your attention www.gamaco.eu PLATINIUM TOWERS - WARSAW POLAND

PT STRUCTURES IN BUILDINGS

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