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UNIDAD I. “INTRODUCCION”

CAPITULO 4. “EVALUACION DE PRODUCTOS CASE”

4.4 Evaluación de productos CASE

Caisson Concrete 3,500 PSI Reinforced:

Concrete strength expressed in PSI (Pounds per square inch) and Metric Units - MPA (Mega Pascal’s)

PSI MPA

Formwork and Rebar Quantities:

Type of

The following rate is for the pumping activity only, excluded final placing of the concrete:

• Per Cubic Yard $8.40 - $13.13 / CY

• Per M3 $11.18 - $17.46 / M3

Formwork: Material cost and man hours per 1 SF of Contact area timber formwork with plywood and timber or metal framing with associated cast in place connections / bolts:

Cost basis 2009

Application Fabricate &

erect &

Isolated Walls 10’ high Materials

$2.81

Rule of thumb for formwork is 10 – 20 SF of formwork per one cubic yard of installed reinforced concrete.

Formwork – Erect, Strip and Repair:

Application Man-Hours

Pre-Cast Concrete Floor Slabs (Elevated) 3,000 PSI Concrete:

Solid or Hollow 3,500 PSI concrete strapped and grouted.

Floor

• Excludes crane costs:

• For areas larger than 25,000 SF / 2,323 M2 multiply installation hours by 0.85

Pre-Cast Concrete Wall 3,500 PSI Reinforced Concrete (Insulated with batt insulation 0.50 – 1.00 inch):

Tilt –up and industrial applications:

Floor Thickness

Material Cost per SF

Installation Man-hours per

SF

Material Cost per M2

Installation Man-hours per

M2

3” 3.75 0.20 40.35 2.15

4” 4.50 0.20 48.40 2.15

5” 5.75 0.25 61.90 2.70

6” 6.50 0.25 69.95 2.70

• Excludes crane costs:

• For areas larger than 25,000 SF / 2,323 M2 multiply installation hours by 0.85

Slab on Grade (SOG) Concrete Floors: includes supply and installation complete with concrete, formwork and rebar, includes 4” thick sub base and polythene.

Thickness of Floor Slab $ SF $ M2

4” - 200 mm 6.67 71.35

6” - 250 mm 8.09 86.99

9” - 225 mm 9.40 101.12

Concrete Walls: includes supply and installation complete with concrete, formwork and rebar.

Thickness of Wall $ SF S M2

4” - 200 mm 20.48 220.50

6” - 250 mm 21.95 236.25

9” - 225 mm 23.42 252.00

Pipe Bridge – Budget Pricing Includes Foundations and Structural Steel (2009 Cost Basis)

Type Materials per LF Man-hours to install per LF

Materials per M

Man-hours to install per M

Light Duty $66.68 1.77 $218.72 5.80

Heavy duty $102.38 2.33 $335.79 7.64

Reinforced Concrete Data:

Using $473 per CY $620 per M3 for installed concrete as a benchmark for concrete: The approximate break out of this cost would be as follows:

Category Cost per CY Cost per M3 Percentage

Concrete $95 $124 20%

Rebar $158 $207 33%

Formwork $221 $289 47% (20% M – 80% L)

Total $474 $620 100%

As a rule of thumb for a quick method of estimating concrete, there is typically 100 – 200 pounds of rebar in 1 CY of reinforced concrete or 55 kg – 110 kg in 1 M3

Use the above ratio’s to determine approximate values for rebar and formwork.

Gunite / Sprayed on Concrete Thickness Material cost

per SF

Installation man-hours per SF

Material cost per M2

Installation man-hours per M2

1” $3.31 0.10 $35.60 1.08

1.5” $3.94 0.12 $42.37 1.29

2.5” $6.77 0.17 $72.87 1.83

3.0” $7.98 0.22 $85.87 2.37

For applications using mesh reinforcement add $0.50 – $1.25 to material cost and add 10% to installation man-hours:

Injection grout / Concrete: (1:3:6) mix: (includes batching plant and pressure pumps, excludes drilling costs)

• $578 - $683 / CY

• $767 - $908 / M3

Concrete General Estimating Data

Bush hammer concrete $0.58 - $1.21 / SF $6.24 - $13.02 / M2 Acid wash concrete $0.21 - $0.35 / SF $2.26 - $3.77 / M2 Pattern concrete slabs $0.47 - $0.79 / SF $5.06 - $8.50 / M2 Colorize concrete slab $0.53 - $0.95 / SF $5.70 - $10.22 / M2 Bag / Dress concrete walls $0.26 - $0.68 / SF $2.80 - $7.32 / M2 Estimating Thoughts for Structural Steel and Miscellaneous Steel

Obtain and review any available engineering deliverables / drawings or sketches. Take off lengths of steel section and multiply by appropriate weight in pounds per LF,

determine pounds / tons of steel that is depicted on the drawings. Structural steel is usually fabricated in a vendors shop, and delivered to the site for eventual erection.

Structural steel has a number of differing specifications / materials of construction, that have differing cost consequences the most widely used is A36.

Issues that may perhaps impact the erection activity of new structural steel are:

• Lifting equipment / cranes / hoists

• Mobilization / de-mobilization of crane (crane are typically rented by the day or week)

• Crane reach

• Lifting capacity

• Number of floors

• Bolted connections

• Welded connections

• Painting / touch up painting

Platforms,ladders, handrails, stair risers and other miscellaneous: perform take off and establish pounds / tons of material and assign appropriate installation man-hours.

Checker plate, grating and floor plate and metal decking: perform take off and establish square feet of material and assign appropriate installation man-hours, allow at least 5%

for waste in the cutting / fit up activity.

Order of Magnitude Structural Steel Estimating Data Structural Steel weights per SF:

Manufacturing Building = 10 - 15 lb / S.F.

5 Floor Office Building = 15 – 25 lb / S.F.

Heavy industrial Facility = 25 – 75 lb / S.F.

Process Structures: Preliminary weights of structures can vary from 1.5 lb to 3.5 lb (Cubic Foot of enclosed area).

Structural Steel as percentage of major equipment cost: usually falls in the 5% to 8% of major equipment cost. The following pie chart delineates the various cost / fabrication and installation activities associated with structural steel.

Percentage Breakout of Structural Steel Based on 500 Ton - 3 story Building

Fabrication 34%

Material Cost

29% Installation

20%

Align & level 2%

Priming paint 8%

Delivery to site 2%

Shop Draw ings 5%

MISCELLANEOUS STRUCTURAL STEEL ITEMS: (Labor & Material Costs, excludes crane and scaffolding costs):

Description Cost per Ton / Pound / SF

Cost per Kg / M2 Structural Steel (Columns and Beams –

100 Ton and above)

$1,961 - $2,650 ($0.99 -

$1.33 per pound)

$1.96 - $2.39 For applications less than 100 Ton

multiply value by 1.15

Light framing steel (tubular and channels)

$2,2374 - $3,021 ($1.19 -

$1.52 per pound)

$2.37 - $3.02 Heavy framing steel (RSJ’s and wide

flange beams) $2,226 - $2,862 ($1.11 -

$1.43 per pound) $2.23 - $2.86 Metal studs / framing $3,021 - $3,445 ($1.52 -

$1.73 per pound

$3.02 - $3.45 Miscellaneous lintels and angles /

channels $2,650 - $3,180 ($1.33 -

$1.59 per pound $2.65 - $3.18 Corrugated metal decking, galvanized 2”

rib 18 g

$1.75 - $2.07 / SF $18.82 - $22.26

Ditto 20 g $1.96 - $2.28 / SF $10.49 - $24.54

Galvanized steel ladders connected to masonry or concrete w/o safety loops.

$41.87 / LF $136.10

Ditto with safety loops $69.43 / LF $225.67

Handrails 1.5” diameter CS 2 rail system 30”- 36” high

$23.85 / LF $77.54

Stairs – galvanized steel 36” wide c/w side plate and handrails (open grating)

$159 - $186 per tread Bollards 3” diameter 6’ long (3’ in ground

filled with concrete)

$477 - $795 each H.D. bolts 1/2” diameter x 8” long $11.13 / Each AVERAGE MH UNITS FOR STRUCTURAL STEEL ERECTION

Structure Type Avg. MH/Ton

Pipe Racks 18-25

Equipment Structures 30-40

Platforms, Walkways, Ladders 45-70

Other Misc. Ironwork 40-80

Adjust Units for Job Conditions, Including Height Factors and size of project.

Average Weights for Misc. Iron

Structure Type Average Weight 1” x 3/16” Bar Type Grating - Galv 8 / 9 # SF / 0.03

M.H.’s / SF:

1 1/4” x 3/16” Bar Type Grating

Galv 9.5 /10.5 # SF /

0.03 M.H.’s / SF

Ladders - W Cage 27 / 30 # LF

Ladders - No Cage 11 / 13 # LF

Stairways - 75 / 85 # LF

2” L - Handrail W Toe Plate 14 / 16 # LF 1 50” Pipe Handrail 13 / 15 # LF Stair Treads Grating1.25” x 3/16”

(9” wide x 3’-0)

25 /30 # each Ditto 1.25” x 3/16” Floor Grating 11 / 12 # / SF Metal Decking Installation

(Roof & U/S of elevated slabs, laid on joists)

Labor only:

Man-hours Man-hours

per SF per M2

1.5" ribbed depth 18g galvanized 0.010 0.108 1.5" ribbed depth 20g galvanized 0.010 0.108 1.5" ribbed depth 22g galvanized 0.010 0.108 3" ribbed depth 18g galvanized 0.013 0.140 3" ribbed depth 20g galvanized 0.013 0.140 3" ribbed depth 22g galvanized 0.013 0.140

Ref

#

Type of Material Fabricate

& Install

M.H’s per LF