SMART REINFORCING BETTER FASTER CHEAPER

Transcription

1 SMART REINFORCING BETTER FASTER CHEAPER MITA (P) 269/06/2003 June 2016 foreword Prefabrication Takes Flight Traditionally, welded wire mesh for slabs and walls can be used to fast track the steel fixing work for a project. However, the conventional concept of welded wire mesh has limitations as the wire diameter is only upto 13mm with the closest spacing fixed at 100mm (area of steel 1328mm 2 /m). To overcome this limitation and to allow prefabrication and use of slab mesh for slabs with heavy loading, we have incorporated single directional mesh upto 25 mm diameter bar in our product range (please refer to page 2 for more details). This allows mesh to be used for heavy slabs or raft foundations that previously can only be reinforced using loose bars. Hence, these solutions can help builders fulfill BCA s requirement of 65% prefabrication for slab. By continuing our efforts to provide Better, Faster, Cheaper reinforcing solutions, BRC strives to support our valued customers as prefabrication takes flight. Lim Siak Meng Group Managing Director 1

2 42 Storey Residential Bu Specification of To support regulatory requirements and to give designers more flexibility to cater to varied slab design requirements, BRC has the following F-mesh solutions for slab: Mesh Main Bar/Wire Cross-Sectional Area Holding Wire Mass Ref. Size mm Spacing mm Main mm 2 /m Size mm Spacing kg/m 2 mm F F F F F F F F F F F F F F F F F F F F F F F F F F F F F x F x F x F x F x F x Better 2 2F x F x

3 ilding at Robinson Road Mesh for Slab F-mesh is a single directional mesh to cater for large spans, heavy slabs. Main rebar upto 40mm is available. Main bar/wire Holding wire a. Horizontal layer b. Add vertical layer. c. Completed slab. Better 3

4 Specification of 42 Mesh Storey for Residential Slab Bu Mesh can be manufactured by combining main and cross wires to suit the varied design requirements for slab and wall as follows: Main Wire Area Mass Size mm (A) Spacing mm (B) mm 2 /m kg/m x x Size mm (C) Cross Wire Area Mass Spacing mm (D) mm 2 /m kg/m x x Faster 4 Nomenclature for specification: H AB CD Eg: H Diameter 13 x Diameter 10 x 200

5 ilding at Robinson Road 18 Storey Mixed Development at Tanjong Pagar - Prefab Household Shelter Wall 50% Time Improvement Original reinforcement details for household shelter wall Faster Household shelter wall specified in D10 mesh. To improve productivity, 8 sheets of mesh were combined and supplied as 5 panels. 2 workers took 20 minutes to install the 5 panels and another 2 hours to insert the loose U links. Time improvement of at least 50% compared to original specification. 5

6 Light Industrial Building at Ayer Raja Original slab detail. Cheaper 6 1. Bottom vertical layer of T F-mesh. 800mm thick raft foundation slab. Reinforcement - T bothways, top and bottom. Total weight - 31 MT covering 500m 2. Single directional F-mesh was used to speed up steel fixing work.

7 h - Raft Foundation Slab Mesh Saved 2 Days Per Cast Saved 2 Days 2. Top layer of F-mesh with bend to cater for slab edge. 3. Raft completed for casting. Cheaper Each sheet of mesh weighed about 150kg. 8 workers took 18 hours over 2 days to complete laying the mesh or 4.7 manhour/mt. Tying loose bars will take at least 4 days. Time savings of 2 days per cast. 7

8 Original beam d 5 Storey Industrial Building 1. Workers guiding the prefab beam into position. Better 8 Heavy prefab beam measuring 1.2m (W) x 0.6m (D) x 11m (L). Reinforcement: 2 x 9 x T40 Top + 9 x T x T32 bottom, 2 x T links. Total weight 5 MT per beam.

9 at Loyang - Prefab Beam 90% Time Savings etail. Slanted mesh for staircase wall. 2. Putting concrete spacers before lowering the prefab beam into formwork Better 5 workers took 15 minutes to install the beam and another 2 hours to tie the loose lapping bars. Tying loose bars will take at least 10 hours. Time savings of 90%. 9

10 3 Storey Terrace Factory at Precast beam sectional and 1. Prefab reinforcement for precast beams ready for delivery. 10 Precast beam for terrace factory. Reinforcement for beam prefabed for quick drop in installation at the precast yard. Each beam weighed between 0.9 MT to 2.5 MT depending on bar and link configuration. Prefab beam formed by loose rebar welded to beam cages.

11 Gul - Prefab/Precast Beam 80% Time Savings reinforcement details. 2. Workers tying loose links to complete the prefab beam before casting at the precast yard. 2 workers took 30 minutes to fix the remaining loose links before hoisting the prefab beam into the mould for inspection and casting. Fixing loose bars conventionally will take at least 4 hours. Time savings of more than 80%. 11

12 8 Storey Warehouse at Tuas South - En Fonda Original slab reinforcement detail. Faster 12 Post-tensioned slab in bays of 60m x 9m. Bottom slab reinforcement: A8 mesh + T Top slab reinforcement: A8 mesh, T loose bar. Additional bottom reinforcement combined into engineered A8 mesh to raise site steel fixing productivity. T top bars converted into mesh for easy laying.

13 gineered Mesh for Post-tensioned Slab Shop drawing for A8 mesh +T10-400(B) equivalent. 1. Bottom A8 mesh combined with equivalent of T reinforcement. 13

14 Sequential Packing 8 Storey Warehouse Fonda at Tuas South - En 2. 6 workers laying the mesh which were packed in sequence to avoid further searching or sorting on site. 3. Bottom mesh for 1 bay completed. 14 For 1 bay, 30 sheets of mesh measuring 7m x 2.4m (500m 2 ) were laid in 2 hours by 6 workers. Original specifications of A8 + T will take at least 6 hours to complete. Time savings of more than 60%.

15 gineered Mesh for Post-tensioned Slab Upto 80% Labour Cost Savings 4. Workers laying T engineered mesh over post tensioned beam instead of loose bars sheets of A8 top mesh (385m 2 ) were completed in 2 hours by 6 workers. Direct workers were used to lay the mesh. Assuming all in labour cost of $12/hour, the cost of laying mesh is about $0.30 to $0.40/m 2. If we add 60% idling time, the cost is still about $1/m 2. This is a huge saving from mesh laying sub-contracting rate of $3 to $5/m 2. 60% to 80% labour cost savings. 15

16 Manufacturing Capabilities Over the pass two years, BRC has relentlessly upgraded our manufacturing capabilities and capacity for prefabricated reinforcement. Our upgraded arsenal consists of: Fully automatic mesh welding lines from Europe. Automated shear lines for rebar cutting from USA, Europe. Automatic double benders from USA, Europe. Automatic link benders from Europe and Japan. BRC ASIA LIMITED Jalan Boon Lay Singapore Telephone enquiries Fax Visit our website at Or us at