Hollow Core Slabs & Panels Prestressed/Precast

1. Hollow Core Slabs & Panels Prestressed/Precast • Definition & Advantages • 2) Applications • 3) Examples – Commercial & Industrial • 4) Examples – Low Cost Housing • 5) Green Building – LEEDS 6) Weiler Gmbh – Precast Engineering & Machinery

2. Hollow Core Definition: • A prestressed, precast, hollow core concrete element, • flat with constant slope, with minimized weight through the • use of longitudinal voids, strengthened with stressed steel cable.

3. 1) Hollow Core Slabs: Advantages: - Speed, simplicity & flexibility of production & assembly – 1000 m2 / day - Controlled & Consistent Quality – Production takes place under controlled conditions, year round. - High Compressive Strengths – 700-900 kgs/cm2 (10000-12500 psi Weiler extruder) - Maximum Economy in materials (40 - 50%), labor & time. - Design Flexibility – clear spans up to 22 meters (70 ft) without columns - Immediate Use when placed as floors on site. - Fire Resistance - 2 to 4 hours - Thermal & Acoustic Resistance - Resistance to humidity, mold, insects and infestations - No need for forming, supports or scaffolding on site. Build in weeks, not months. - No need for compressive layer of concrete (depending on application and regulation)

5. 2) Applications Rail Landing Docks & Moorings Earth Retention

6. 2) Applications Tunnel & Canal Coverage

7. 2) Applications Warehouse, Storage & Light Industrial Buildings

8. 2) Applications Walls for Warehouses/Storage

9. 2) Applications Silos

10. 2) Applications Parking

11. 2) Applications Stadiums Stands / Seating

12. 2) Applications Liguid Storage / Water Treatment

13. 3) Building Examples Al Jazeera Tower – Qatar Hollow Core Slabs - 11,000 m2 - 15cm slab - 680 m2 - 26cm slab

14. 3) Building Examples Burj Residences – Dubai Hollow Core Slabs - 38,000 m2 - 22cm slab

15. 3) Building Examples Hollow Core Slabs - 37,000 m2 - 26cm slabs Al Salam Tower & Parking

16. 3) Building Examples Wafi Hotel Dubai Hollow Core Slabs : - 100,700 m2 - slabs 20, 26 & 32cm

17. 3) Building Examples Twin Towers Qatar Hollow Core Slabs - 25,000 m2 15 & 20cm slabs

18. 3) Building Examples Dubai Doha Tower Hollow Core Slabs - 100,900 m2 various slab sizes

19. 3) Building Examples Bahrain Chamber of Commerce Hollow Core Slabs - 15,300 m2 - 15cm slab - 2,400 m2 - 20cm slab

20. 3) Building Examples Barwa City Residences Qatar Hollow Core Slabs - 360,000 m2 – various sizes - 1,200 m2 floor placed per day.

21. 3) Building Examples Brilliant Star Towers Hollow Core Slabs - 59 floors, 6 days per floor

22. 3) Building Examples Emirates Commercial Centre Hollow Core Slabs - 45,000 m2 - 26cm slab - 75,000 m2 - 22cm slab - 6,900 m2 - 40cm slab

23. 3) Examples Public Works: Schools Generalitat Catalunya Spain

24. 4) Low Cost Housing Mini Slabs and Panels for DIY Construction: Super light sections, slab heights 8, 10 & 12cm (3”, 4”, 5”) & variable widths of 30, 60 & 120 cm (12”, 24” & 48”).

25. 4) Low Cost Housing – Optimized Design for Hollow Core Slabs & Panels

26. 5) Green Building – Energy Consumption Savings of 30-50%

27. Use thermal mass and hollow cores of concrete slabs for night pre cooling and pre heating Release stored heat/cooling to minimize peak load demand Displace energy consumption to off-peak electricity rates Energy consumption savings of 30-50% in hot and cold climates Reduced HVAC machinery & ducting saves 50% on equipment costs In wide use in Europe and Middle East All building types, industrial, commercial, schools, institutions, residencial Leeds Certification 5) Green (Hybrid) Buildings

28. 5) Green Building – Savings Example Jeddah Building - Area 32000 m2 Original Design Capacity Air Conditioning: 2200 Tons + 550 Tons safety margin Revised Design with Green Radiant Panels: 750 Tons + 250 Tons safety margin Peak Consumption with Radiant Panel, August 2004: 530 Tons

29. 6) WEILER Gmbh Since 1954 – Engineering & Machinery for Precast Concrete • Pioneer and leader in long bed precast • concrete technology • Over 230 plants y 500 installed machines • around the world • A complete range of machinery and • engineering services adapted to the • needs of individual clients • Tough, precision machinery, designed and • built to last a lifetime • Highest European quality standards – all components • supplied by leading global brands (Siemens, Bosch, SKF, ABB etc.) • Local service programs supporting clients during all stages • of factory growth

31. Products • Extruder – exclusively for prestressed hollow core slabs & panels • Slipformer – solid and hollow core slabs, beams & other prestressed • products • Tilting Tables – for walls and panels • Production Equipment – batching plants, saws, overhead cranes, bed cleaners, concrete transport systems, prestressing equipment, accessorios etc. • Services • Complete engineering and support services, turnkey plants, training, parts etc

32. Extruder • maximum productivity at lowest production cost • hollow core slabs 8 to 50 cm thick • 6-8 hours cure to cut (w/ dry mix concrete & heated beds) • hollow voids to 50% of volume • minimum cement consumption – 320-350 kgs/m3 • highest compressive strength in the market - 650-900 kg/cm2 (12,500 psi)

33. Slipformer • maximum production flexibility: solid & hollow core slabs/panels, beams, cement piles, posts, lintels, etc. • 20-30% savings compared with wet mix precast • 14-16 hours cure to cut (with heated bed & dry mix concrete) • cement consumption - 340-380 kgs/m3 (575- 640 lbs/cu yrd) • high compresive strength 450-550 kgs/cm2(6400psi)

34. Slipformer – Products • Solid and hollow core slabs, 6 to 50cm (2.5 to 20”) • T Beams – up to 40 cm height (16”) • Piles – up to 50 X 50cm (20 X 20”) • Lintels • Walls & sound barriers • Sandwich Panels • Roofing elements • Custom Products

35. Compaction Systems Slipformer Extruder

36. Direct Cost Comparison – Slab / Panel Production – Extruder / Slipformer 1) For the same slab height, extruded slabs are 12 to 32% lighter than slipformed slabs. 2) Extruded slab cement consumption is minimized,from 320-350 kgs/m³, compared to 400-450 kgs/m³ for the slipformer.Cement savings of 100 kgs/m³ . 3) Extruded slabs have higher compressive strengths, 10000 psi(extruder) compared to 8000 psi(slipformer) 5) Combining lighter slabs using less concrete, higher compression & minimal cement consumption, savings on production costs are 30 to 60% when using the extruder.

37. Battery Mold for Walls & Panels

38. Tilting Tables

39. ENGINEERING • Plant modifications & expansions • Transition to semiautomatic & automatic production systems • Turn Key installations, startup, personnel training etc. • Plant conception & design • Production Management • Custom precast products

41. Mini Slabs & Panels for DIY Construction / Low Cost Housing

42. A complete range of products and services from a top tier supplier • 50 years of globalexperience in long bed precast production • One machine or a complete plant – Weiler is a committed, long-term partner for growth & profit

43. Hollow Core Slabs & Panels Advantages and Examples June 2010A. Powell Jacquier Lic. MBA