SimpleTabs
 
  • Overview
  • Advantages-Money
  • Advantages-Time
  • 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.

    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%

    WWR applications indicate lower installation times. Two independent studies performed time comparison between WWR and reinforcing steel in different applications. This information is described below.

     
Technology
All processes have imported machinery with high end technology, PLC based automation,
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Applications
Welded Wire Mesh has a wide range of aplications across several sectors
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Design Capability
A pioneering approach from IJM steel which goes to display the thought leadership of IJM.
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