Hollow Core Slabs & Panels Prestressed/Precast

1) Definition & Advantages

2) Applications

3) Examples – Commercial & Industrial

4) Examples – Low Cost Housing

5) Green Building – LEEDS

6) Weiler Gmbh – Precast Engineering & Machinery

1) 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.

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)

2) Applications

Docks & MooringsRail Landing

Earth Retention

2) Applications

Tunnel & Canal Coverage

2) Applications

Warehouse, Storage & Light Industrial Buildings

2) Applications

Walls for

Warehouses/Storage

Silos2) Applications

Parking2) Applications

Stadiums2) Applications

Stands / Seating

Liguid Storage / Water Treatment

2) Applications

3) Building Examples

Hollow Core Slabs - 11,000 m2 - 15cm slab - 680 m2 - 26cm slab

Al Jazeera Tower – Qatar

3) Building Examples

Hollow Core Slabs - 38,000 m2 - 22cm slab

Burj Residences – Dubai

3) Building Examples Hollow Core Slabs - 37,000 m2 - 26cm slabs

Al Salam Tower & Parking

3) Building Examples

Hollow Core Slabs : - 100,700 m2 - slabs 20, 26 & 32cm

Wafi Hotel Dubai

3) Building Examples

Hollow Core Slabs - 25,000 m2 15 & 20cm slabs

Twin Towers Qatar

3) Building Examples

Hollow Core Slabs - 100,900 m2 various slab sizes

Dubai Doha Tower

3) Building Examples

Hollow Core Slabs - 15,300 m2 - 15cm slab - 2,400 m2 - 20cm slab

Bahrain Chamber of Commerce

3) Building Examples

Hollow Core Slabs - 360,000 m2 – various sizes - 1,200 m2 floor placed per day.

Barwa City Residences Qatar

3) Building Examples

Hollow Core Slabs - 59 floors, 6 days per floor

Brilliant Star Towers

3) Building Examples

Hollow Core Slabs - 45,000 m2 - 26cm slab - 75,000 m2 - 22cm slab - 6,900 m2 - 40cm slab

Emirates Commercial Centre

3) Examples Public Works: Schools

GeneralitatCatalunyaSpain

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”).

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

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

5) Green (Hybrid) Buildings

• 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 Building – Savings Example Jeddah Building - Area 32000 m2

Original Design Capacity Air Conditioning: 2200 Tons + 550 Tons safety marginRevised Design with Green Radiant Panels: 750 Tons + 250 Tons safety marginPeak Consumption with Radiant Panel, August 2004: 530 Tons

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

Since 1954 – Engineering & Machinery for Precast Concrete

6) WEILER Gmbh

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

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)

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 (6400 psi)

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

Compaction Systems

Extruder Slipformer

Direct Cost Comparison – Slab / Panel Production – Extruder / SlipformerPeralte 16" x 48" - 40 x 120 cm

16" / 40cm area cm² volumen m³/m² diferencia % peso/m² costo hormigón/m² costo hormigón 100k m² diferencia %Weiler 2262 0.1885 446.93 MXN 127.76 MXN 12,775,902 Spancrete 2857.1 0.2381 26.31% 564.52 MXN 193.81 MXN 19,380,525 51.70%

401 in²

Peralte 12" x 48" - 30 x 120 cm

12" / 30 cm area cm² volumen m³/m² diferencia % peso/m² costo hormigón/m² costo 100,000 m² diferencia %Weiler 1806.12 0.1505 356.86 MXN 102.01 MXN 10,201,066 Spancrete 2038 0.1698 12.84% 402.67 MXN 138.24 MXN 13,824,336 35.52%

316 (Ultra Light Spancrete)

Peralte 10" x 48" - 25 x 120 cm

10" / 25 cm area cm² volumen m³/m² diferencia % peso/m² costo hormigón/m² costo 100,000 m² diferencia %Weiler 1459.6 0.1216 288.39 MXN 82.44 MXN 8,243,902 Spancrete 1667 0.1389 14.21% 329.37 MXN 113.08 MXN 11,307,737 37.16%

277 in² (Ultra Light Spancrete)

Peralte 8" x 48" - 20 x 120 cm 8" / 20 cm area cm² volumen m³/m² diferencia % peso/m² costo hormigón/m² costo 100,000 m² diferencia %Weiler 1218 0.1015 240.66 MXN 68.79 MXN 6,879,332

Spancrete 1513 0.1261 24.22% 298.94 MXN 102.63 MXN 10,263,111 49.19%251 in²

Peralte 6" x 48" - 15 x 120 cm 6" / 15cm area cm² volumen m³/m² diferencia % peso/m² costo hormigón/m² costo 100,000 m² diferencia %Weiler 930 0.0775 183.75 MXN 52.53 MXN 5,252,692 Spancrete 1170 0.0975 25.81% 231.17 MXN 79.36 MXN 7,936,444 51.09%

197 in²

Peralte 4" x 48" - 10 x 120 cm 4" / 10 cm area cm² volumen m³/m² diferencia % peso/m² costo hormigón/m² costo 100,000 m² diferencia %Weiler 672.2 0.0560 132.82 MXN 37.97 MXN 3,796,623Spancrete 890 0.0742 32.40% 175.85 MXN 60.37 MXN 6,037,124 59.01%

138 in²

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 .

5) Combining lighter slabs using less concrete, higher compression & minimal cement consumption, savings on production costs are 30 to 60% when using the extruder.

3) Extruded slabs have higher compressive strengths, 10000 psi(extruder) compared to 8000 psi(slipformer)

Battery Mold for Walls & Panels

Tilting Tables

Plant conception & design

Production Management

Custom precast products

Plant modifications & expansions

Transition to semiautomatic & automatic production systems

Turn Key installations, startup, personnel training etc.

ENGINEERING

Mini Slabs & Panels for DIY Construction / Low Cost Housing

A complete range of products and services from a top tier supplier

50 years of global experience in long bed precast production

One machine or a complete plant – Weiler is a committed, long-term partner for growth & profit

Hollow Core Slabs & Panels Advantages and Examples

June 2010A. Powell Jacquier Lic. MBA