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SMART REINFORCINGBETTER • FASTER • CHEAPER

foreword

MITA (P) 269/06/2003

Nov 2014

Make Room for Ideas!In 1943, Ingvar Kamprad, then 17, started IKEA, the company that would go on to revolutionalise the furniture industry by introducing flat pack and self assembled furniture. Their tagline – Make Room for Ideas!

Fast forward 71 years, IKEA now the world’s largest furniture manufacturer boosts 351 stores in 43 countries, giving common folks access to well design and functional furniture at affordable prices.

Locally, we at BRC, started the prefabrication of reinforcement in the 1990s.

The idea was to provide prefabricated reinforcing elements for quick drop in installation on site. This result in tremendous savings in manpower and time as the prefabrication is done off site on “borrowed” time. In addition, we employ fully mechanized and industrialised processes in our factories to achieve a much higher level of productivity and efficiency.

Conceptually, this philosophy is very similar to containerization of cargo for shipment. Everything is pre-packed off site. In this way, the port is able to fully mechanise and computerise the handling of standard boxes and turnaround the vessels very quickly.

Prefabrication is now the mainstay of our government’s productivity drive and an important component of BCA’s buildability and constructability requirements. By going the prefabrication route, the construction industry is taking a big leap forward in achieving sustainable improvement in productivity and significant reduction in manpower.

In this issue, we feature several case studies on time savings ideas, notably prefabricated transfer beams that saved 2 weeks for the contractor.

Given the increasing rate of adoption by contractors, we believe that prefabricated reinforcement will become an ubiquitous construction product in the very near future.

Aspiring to build “Better, Faster, Cheaper” Lim Siak MengGroup Managing Director

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• Prefab column for basement of size 0.9m (W) x 0.5m (L), weighing 0.8 MT to 1.0 MT.• Each column installed in 10 minutes by 3 workers.

Bet

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Condominium Development at Boon Lay Way - Prefab Column

Columns ready for inspection before closing formwork for concreting.

Saved 2 Days

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Fonda

• 50 prefab columns for 1 block completed in a day.• Shortened construction duration by 2 days.

Bet

ter

Condominium Development at Boon Lay Way - Prefab Column

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Fast

er

• Slab reinforcement of T10-200 both ways for top and bottom with additional rebars at certain locations.• Reinforcement converted to large sheets of mesh to maximize productivity on site. • Total mesh weight - 3.0 MT.• 8 workers took 3 hours to lay bottom mesh and 4 hours to lay top mesh.

Condominium Development at Boon Lay Way - Slab Mesh

Original bottom reinforcement detail.

1. Bottom mesh completed in 3 hours.

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Fast

er • Productivity is 19 manhour/MT.• Conventional method will take 8 workers 2 days to complete or 64 manhour/MT.• Time savings of 1 day per floor.

Condominium Development at Boon Lay Way - Slab Mesh

Original top reinforcement detail.

2. Slab completed, ready for casting.

8 Day Cycle Achieved

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Che

aper

Fonda42 Storey Residential Building at Robinson RoadCondominium Development at Boon Lay Way - Prefab Storey Shelter Wall

• Staircase shelter wall of nominal size of 9.0m (W) x 4.35m (L).• Reinforcement – T13-100 both ways.• Total weight – 8.0 MT.

Original bottom reinforcement detail.

Original bottom reinforcement detail.

1. Panalised wall reinforcement ready for installation.

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Che

aper

42 Storey Residential Building at Robinson RoadCondominium Development at Boon Lay Way - Prefab Storey Shelter Wall

• 22 panels took 4 workers 4 hours to complete installing.• Tying of rebar will require scaffold and will take 6 workers 3 days to complete.• Time savings of 2 days.

4. Storey shelter wall completed with 22 prefab panels.

3. Panel guided into position by workers.2. Prefab panel being hoisted.

Saved 2 Days Per Floor

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Fonda42 Storey Residential Building at Robinson Road

• Storey shelter wall measuring 8.8m (L) x 3.1m (W).• Reinforcement – T13-100 both ways for inner face and T10-100 both ways for outer face.• Total weight – 3.2 MT.• Full set of wall consisting of 34 sheets of mesh/u-mesh installed in 6 hours by 3 workers or 6 manhour/MT. Bet

terExecutive Condominium Development at Sengkang - Storey Shelter Wall Mesh

1. Prefabricated wall consisting of flat mesh, u-mesh and loose bars.

Original reinforcement detail.

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42 Storey Residential Building at Robinson Road

• Manually tying loose bars will take 4 workers 3 days to complete or 45 manhour/MT.• Time savings of 2 days per floor.Bet

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Executive Condominium Development at Sengkang - Storey Shelter Wall Mesh

2. Placing u-mesh in place by workers without crane.

3. Completed storey shelter wall.

Saved 2 Days Per Floor

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Fonda

• Prefab transfer beam measuring 3.4m (D) x 1.0m (W) x 8.0m (L).• Prefabricated beam weighing 5.3 MT installed in 15 minutes by 3 workers.• Workers took another 3 hours to add in dowel/connecting bars.Fast

erHotel Development at Victoria Street - Prefab Transfer Beam

Original reinforcement detail.

1. 3.4m tall by 1.0m wide prefab transfer beam being hoisted into position.

Saved 14 Days

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• Tying rebar will take 6 workers 3 days to complete 1 beam as scaffold has to be erected as a working plaform and for safety reasons.• Saves 2 days per beam and a total of 14 days for the transfer floor.Fast

erHotel Development at Victoria Street - Prefab Transfer Beam

Original reinforcement detail.

1. 3.4m tall by 1.0m wide prefab transfer beam being hoisted into position. 2. Prefab beam detailed for connecting with dowel bars on site.

NEW!

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• Slab specified with D13 mesh for bottom reinforcement and A12 mesh for top reinforcement with additional bars at certain locations.• Mesh supplied as single directional F- mesh for easy laying and to minimise lap.• 8 workers took 6 hours to lay the bottom mesh and 8 hours to lay the top mesh. Total area covered is 400m2.Che

aper

Original slab reinforcement detail.

Hotel Development at Victoria Street - Slab Mesh

1. Single directional F-mesh used for easy laying and to minimise lapping.

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2. Bottom mesh completed in 6 hours.

8 Day Cycle Achieved

• Total mesh weight – 8.5 MT.• Productivity is 13 manhour/MT.• Achieved a cycle time of 8 days per floor.Che

aper

Hotel Development at Victoria Street - Slab Mesh

3. Completed slab.

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9 Storey Multi-user Industrial Development at Buroh Crescent - Prefab Ramp Beam

STAIR-5

VOID

VOID

2ND STOREY PLAN

PR

• Ramp beam measuring 0.8m (D) x 1.0m (W) x 12m (L).• Weight – 4.9 MT.• Installed in 15 minutes by 4 workers and another 2 hours to position anchorage bars at both ends in place.• Conventional tying will take 4 workers 2 days to complete.• Time savings of 1.5 days per beam.

NEW!

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9 Storey Multi-user Industrial Development at Buroh Crescent - Prefab Ramp Beam

1. Installation of prefab ramp beam in progress.

2. Completed ramp beams with anchorage bars in place.

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9 Storey Multi-user Industrial Development at Buroh Crescent – Post-tensioned Slab Mesh

• Post-tensioned slab area measuring 600 m2. • Total mesh weight – 4.6 MT.• 4 workers took 1.5 hours to lay bottom mesh and 3 hours to lay top mesh.• Productivity is 4 manhour/MT.• Tying loose bars will take 2 days or 21 manhour/MT.• Time savings of 80%.

1. Bottom mesh with additional bars incorporated laid in 1.5 hours.

2. Top mesh completed in 3 hours.