- Codes
- Additional Resources
 Indian Codes |
Code |
Title of the Code |
Edition |
|
IS 456
|
Plain and Reinforced Concrete – Code of Practice |
2000 |
|
IS 1566 |
Specifications for Hard Rolled Steel Wire for Concrete Reinforcement |
1982 |
|
IS 432, Part II |
Specifications for mild steel and medium tensile steel bars and hard rolled steel wires for concrete reinforcement |
1982 |
| SP 34 |
Handbook on Concrete Reinforcement and detailing |
1987 |
| IS 7887 |
Mild steel wire rod for general engineering purpose – Specification |
1992 |
|
IS 1599 |
|
1985 |
|
|
Specification for High strength deformed steel bars and wires for concrete reinforcement |
2008 |
|
IS 13920 |
Ductile detailing of Reinforced Concrete Structures subjected to Seismic Forces – Code of Practice |
2002 |
|
IS 1716 |
Method for Reverse bend Test for Metallic Wire (Second Revision) |
1985 |
| International Codes |
Code |
Title of the Code |
Edition |
|
MS 145
|
Welded Steel Fabric for The Reinforcement of Concrete Specification | 2006 |
|
ACI 318
|
Building Code Requirements for Structural Concrete (ACI 18-08) and Commentary |
2008 |
|
BS 8110
|
Part 1 Code of Practice for Design and Construction |
1985 |
|
BS 4482 |
Specification for cold reduced mild steel wire for the reinforcement of concrete |
2005 |
|
BS 4483 |
Specification for welded steel fabric for the reinforcement of concrete . | 2005 |
|
NZ-3109
|
|
1997 |
Table 1 Shows the total cost (material and labor) for each option. Notice WWR material cost is higher than rebar. Even with higher material costs it is more economical than rebar.
-- Table 1 --
Cost Items |
Placement Method |
Traditional Rebar |
WWM D12 Manual (8 x 18 ft)
|
WWM D12 Mechanical (8 x 40 ft) |
| Material |
|
|
|
| Qunatity (t) |
45.7 |
44.5 |
43.0 |
| Unit Cost (dollars) |
600.00 |
750.00 |
750.00 |
| Total base cost (dollars) |
27,420.00 |
33,375.00 |
32,250.00 |
| Total cost including 10% O&P (dollars) |
30,162.00 |
36,712.00 |
35,475.00 |
| Labor |
|
|
|
| Productivity(man-hours/t) |
18.8 |
4.0 |
1.4 |
| Crew |
|
|
|
| Foreman |
1 at $22.00 |
1 at $22.00 |
1 at $22.00 |
| Skilled labores |
4 at $22.00 |
5 at $22.00 |
2 at $22.00 |
| Unskilled labores |
4 at $22.00 |
8 at $22.00 |
2 at $22.00 |
| Crew cost (dollars/hr) |
162.00 |
242.00 |
92.00 |
| Total Crew time(hrs) |
96 |
13 |
12 |
| Total bare installation (dollars) |
15,552.00 |
3,146.00 |
1,104.00 |
| Total labor cost including 20% O&P ($) |
18,662.00 |
3,775.00 |
1,325.00 |
| Equipment |
|
|
|
| Crane (for placement only) |
0 |
0 |
1 |
| Cost including operator ($day) |
0.00 |
0.00 |
1,182.00 |
| Total euipment cost inlucding 20% O&P ($) |
0.00 |
0.00 |
2,128.00 |
| Total work days (work days) |
12.0 |
1.5 |
1.5 |
| Total cost ($) |
48,824.00 |
40,487.00 |
38,928.00 |
| Cost Savings (%) |
|
18 |
21 |
Table 2 Shows the cost comparison for each option adding WWR material waste cost and a higher labor cost. WWR is still more economical with both adjustments.
-- Table 2 --
Cost Items |
Placement Method |
Traditional Rebar |
WWM D12 Manual (8 x 18 ft)
|
WWM D12 Mechanical (8 x 40 ft) |
| Material |
|
|
|
| Original total cost including 10% O&P ($) |
30,162.00 |
36,712.00 |
35,475.00 |
| 5% waste for WWR |
|
1,836.00 |
1,774.00 |
| Adjusted total cost including 10% O&P ($) |
30,612.00 |
38,548.00 |
37,249.00 |
| Labor |
|
|
|
| Original average crew cost ($mhr) |
21.60 |
21.74 |
22.10 |
| Original total labor cost including 20% O&P ($) |
18,662.00 |
3,775.00 |
1,325.00 |
| Adjusted average crew cost ($/mhr) |
36.70 |
36.70 |
36.70 |
| Adjusted labor productivity (mhrs/t) |
15.40 |
|
|
| Adjusted total labor cost including 20% O&P ($) |
25,829.00 |
6,679.40 |
2,202.00 |
| Equipment |
|
|
|
| Total equipment cost including 20% O&P ($) |
|
|
2,128.00 |
| Total cost ($) |
|
|
|
| Original total cost ($) |
48,824.00 |
40,487.00 |
38,928.00 |
| Total cost with 5% WWR waste ($) |
48,824.00 |
42,323.00 |
40,702.00 |
| Total cost with adjusted labor rates ($) |
55,991.00 |
43,391.00 |
39,805.00 |
| Total cost with combined effect ($) |
55,991.00 |
45,227.40 |
41,579.00 |
| Cost Savings (%) |
|
|
|
| Original cost savings ($) |
|
18% |
21% |
| Savings with 5% WWR waste (%) |
|
13% |
17% |
| Savings with adjusted labor rates (%) |
|
23% |
29% |
| Savings with combined effect (%) |
|
19% |
26% |
1. Because bars are welded in a mat, the bars do not move when concrete is placed, insuring bars are in their proper position.
2. Since WWR is prefabricated and welded in plants, the risk of missing a bar is minimized.
3. The chance of improper bending of bars is reduced by using WWR since bending machines bend the mat as a single unit.
4. The use of WWR minimized the chance of misplacement since only one type of mat is used on a given section.
5. Provide the exact size of reinforcement where needed through variable bar size and spacing, thereby reduces steel waste.
6. Any wire size can be used from, starting at W 1.4 up to W 46.5 in increments of 0.1.
7. No site space needed for steel assembly. View example.
8. Faster erection time means you can beat changing weather conditions.
9. Removes reinforcement placement from the critical path.
10. Less field labor needed.
11. The material fabrication is automated.
12. With faster construction, insurance premiums are reduced. For example on bridge deck construction the barrier walls can be constructed faster reducing the time for fall exposure and reducing insurance premium.
13. WWR can reduce construction time, thereby saving: Crane rental time
Equipment leasing Increasing bonus
14. Lower material cost because not fabricating small bar. For example, for a #3 bar the cost is $5/ 100 wt. while a #6 bar is $1.25/ 100 wt.
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