construction estimates

2014

CONSTRUCTION ESTIMATES2014

2014

Estimates

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2014

Estimates

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Point of the illustration?

Document your assumptions.

2014

Estimate Types

Programming– The project is in the concept phase. No schematic and little details

are known. Schematic– Known• Geometrics (alignments V & H, super-elevations, typical sections), field

survey, environmental constraints, traffic loading, bridge span length, retaining wall, etc.

– Unknowns• Final pavement design, phases of construction, detours, utility conflicts,

final quantities Final Plans– All quantities are known, the unknown unknown is the only unknown – Required to be within 3% of the lowest bid (or write a justification)

Contractors Estimate– Estimate based on the individual (contractor’s unique position)

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2014

Bryan District Average Cost

Grade Separation

2 Lane to 4 Lane

2 Lane to Super 2 (passing zones)

Signal

Ramps

Freeway – Controlled Access

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$ 10 Million

$ 2.3 Million/ Mile

$ 1 Million/ Mile

$ 150,000

$ 450,000/ EA

$ 12 Million/ Mile

2014

Programming

Basic estimate (Programming to preliminary Schematic)– Structures (bridges, culverts, storm drains)– Pavement • $/ mi (spread sheet)

– Signals ~ $ 150k/ EA– Miscellaneous (erosion control, striping, signs, traffic control,

etc.) • 10 – 20 % of known (subtotal 1)

– Engineering Contingencies• 6 – 11 % subtotal 2

– Mobilization• 10 % subtotal 3

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2014

Structures

Structures (400)– Culverts (Item 462)– Reinforced Concrete Pipe (Item 464)– Inlets/ Manholes (Item 465)– Headwalls/ Wingwall (Item 466)– Safety End Treatment (Item 467)– Retaining Walls (Item 423)

Average bid for items– Go to www.txdot.gov search “low bid” – Or http://

www.txdot.gov/inside-txdot/division/general-services/bidding/average-low-bid-unit-prices.html

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2014

Structures

Superstructure (beam type)– http://

www.txdot.gov/inside-txdot/division/bridge/specifications/super-design.html

Unit cost found here– http://www.txdot.gov/inside-txdot/division/bridge/unit-cost.html

General programming estimate (for most structures, if specialized design use the links above for more information)– Bridge • Cost = $ 75/ sf deck – includes all structure cost substructure and superstructure

– Culvert• Cost = low bid cost x length x 1.4– 1.4 factor adjust for head wall, wing wall, special trenching, junctions etc.

– Embankment = $ 10/ cy – Excavation = $ 3/ cy– Wall = $ 50/ sf

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2014

All items

100 – Earth Work and Landscape 200 – Subgrade Treatments and Base 300 – Surface Courses and Pavement 400 - Structures 500 - Miscellaneous Construction 600 – Lighting, Signing, Markings, and Signals 700 – MaintenanceSpec Book http://ftp.dot.state.tx.us/pub/txdot-info/des/specs/specbook.pdf

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2014

Pavement cost / mi

See estimate spreadsheet (2014_est.xls)

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2014

Further considerations

Considerations when Estimating Bridge Projects1. Is stage construction necessary?2. Is the replacement bridge on new alignment or the same?3. Will the replacement bridge have longer spans with deeper

beams? If so, will the grade have to be raised for clearance (hydraulics or V.C.)?

4. Will the contractor need special equipment for the project?5. Is a shoofly structure required for a railroad underpass?6. Will a pump station be required?7. Is there a shortage of materials (steel)?8. Is a relief structure also necessary?

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2014

Local Projects

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2014

Local Projects

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Construction = $ 5.9Million

2014

Local Projects

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2014

Local Projects

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Construction = $ 23.5 M

2014

Local Projects

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2014

Local Projects

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Construction = $ ?? M

2014

Local Projects

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