willamette river bridge advisory committee 02.05 - … river bridge advisory committee 02.05.09....
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Willamette River Transit BridgePortland - Milwaukie Light Rail Willamette River Bridge
Willamette River Bridge Advisory Committee 02.05.09
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
• Context
• Scale
• Pedestrian Experience
Shima-Maruyama Bridge
Tokyo, Japan
Concerns we heard:
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
Design Principles - Commitments
• To enliven the pedestrian experience
Pont de Bourgogne Chalon, France
Customization• As a response to contexts
Detail - Integrated Design• To address all scales
Transparency and Intimacy
Willamette River Transit Bridge
Possible Response
Cable-Stayed BridgesArt of the Possible
Customization
Willamette River Transit Bridge
Possible Response
Cable-Stayed BridgesArt of the Possible
Customization
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
Possible ResponsesDetail/Total Design
Willamette River Transit Bridge
Pedestrian ExperienceRange of Responses
Cable-Stayed BridgesArt of the Possible
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
Next Steps – Preliminary Engineering
Pier/Span Arrangement Final• Affect on height
• Affect on pier shallow water footprint
Section Final• Path width and configuration
• Overlooks
Willamette River Transit Bridge
Tower Configuration Final• Refine concepts
• Generate other concepts
Connection Detailing
Furnishings and Finishes
Cable-Stayed BridgesArt of the Possible
Next Steps – Preliminary Engineering
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
Next Steps – Preliminary Engineering
Implement Design Guidelines• Customization
• Detail – Integrated Design
• Transparency and Intimacy
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
Design Principles - Commitments
• To enliven the pedestrian experience
Pont de Bourgogne Chalon, France
Customization• As a response to contexts
Detail - Integrated Design• To address all scales
Transparency and Intimacy
Willamette River Transit Bridge
Questions to Answer:
Cable-Stayed BridgesArt of the Possible
What contexts, beyond bridges, can inform the design?
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
How are large elements integrated into a city without overpowering?Questions to Answer:
Willamette River Transit Bridge
0’
50’
100’
150’
200’
250’
300’
125’
CS
4 –
254’
CS
2 –
277’
Height Comparison
350’32
5’
250’
South Waterfront Wav
e –
120’
Tram 195’
Willamette River Transit BridgeComparison
270’ 254’ 277’
Steel Bridge Cable Stayed - 4 Cable Stayed - 2
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
What is the maximum transparency (spans) and intimacy (towers) that can be provided ?
Questions to Answer:
Willamette River Transit BridgeCable-Stayed BridgesArt of the Possible
How will these concepts inform an integrated design?Questions to Answer:
Willamette River Transit Bridge
• Met with Oregon Iron Works (OIW)
Cost Analysis
• Met with Hepp Steel Resources
• Met with Oregon Steel Mills (now Evraz)
Recent Activities
• Reviewed costs with other outside resources
• About 60% of the cost of wave related to steel
• About 25% of the cost of cable stayed related to steel
Willamette River Transit BridgeCost Analysis
• Team worked to verify estimates
Recent Activities
• Team worked to verify material availability
• Reviewed historical steel price trends
• Reviewed schedule implications of steel fabrication
Willamette River Transit Bridge
• Reconciled quantities and unit prices
Cost Analysis
Verified Estimates
• Steel prices used reflect current market cost
Willamette River Transit Bridge
• Reconciled quantities and unit prices
Cost Analysis
• Steel installed prices include:
– Price from mill
Verified Estimates
– Freight cost from mill to fabrication shop
– Fabrication cost and margin
– Freight costs from fabrication shop to job site
– Contractor installation costs and margin
Willamette River Transit Bridge
• 4” HPS available from only one source – Mittal Steel
Cost Analysis
• Thinner HPS available from SSAB Products
– SSAB focuses on production of standard products
Verified Material Availability
– Low probability of bidding work
– Thinner material requires more labor to laminate
– Laminating material not economically viable
– This would be a special run
Willamette River Transit Bridge
• 4” HPS available from only one source – Mittal Steel
Cost Analysis
• Oregon Steel Mills (now Evraz)
– Currently can not supply “Buy America” steel
Verified Material Availability
– Have never produced 4” HPS
Willamette River Transit Bridge
• 100% Design Shop Drawings Material Procurement
Cost Analysis
• Then Fabrication and Installation
• Construction duration analysis conclusions:
Analyzed Schedule Implication of Steel Fabrication
– 6 month increase high level of certainty
– 6 additional months for a total of 12 possible
– Acceleration of fabrication not viable per OIW
Willamette River Transit Bridge
• Quantity based estimate
Cost Analysis
• Contractor engineering
Cost Estimate Include
• Contingencies
• Differential items
– Requirements Risk
– Bid and Market Risk
– Design Development Risks
Willamette River Transit BridgeCost Estimate
TriMet’s Estimates
Reviewed National Constructors Groups’ Backup
Adjusted labor costs, production rates, equipment costs, permanent and temporary material costs and contractor
margin as needed per recent findings
Willamette River Transit BridgeCost Estimate
Design Build Contractor Engineering
Cost to advance design from
Preliminary Engineering to Final Design
Plus
Cost for Contractor Construction Engineering
Willamette River Transit BridgeCost Estimate
Design Build Contractor Engineering
Same percentage used for all types
Willamette River Transit BridgeCost Estimate
Contingencies composed of three main items
Requirements Risk
Bid – Market Risk
Design Development Risk
Willamette River Transit BridgeCost Estimate
Requirements Risk
Items know but not included in construction cost line
Examples
Address water line – Supplemental greenway work
Willamette River Transit BridgeCost Estimate
Bid – Market Risk
Factors affecting bid climate
Examples
Bridge complexity – Bidder experience
Number of bidders
Willamette River Transit BridgeCost Estimate
Design Development Risk
Difference between estimating what is shown today
versus
Contractor bid prior to contract award
Willamette River Transit BridgeCost Estimate
Costs that are different between alternatives
Extended overhead for 6 months
$4.5M
Supplemental Owner Engineering
$1.4M
Willamette River Transit BridgeCost Estimate
Totals do not include
Construction financing costs
Steel escalation cost if bid during peak market
Willamette River Transit BridgeCost Estimate
Funding calculated with mid-point of construction values
Year of Expenditure (YOE)
August 2013
Willamette River Transit BridgeCost Estimate Discussion – Questions?
Wave$176 M
CS 4 Pier$102 M
CS 2 Pier$113 M