pedestrian walkback tunnel, finishes package washington dulles international airport
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Dulles Pedestrian Walkback Tunnel, Finishes Package Washington Dulles International Airport. Pedestrian Walkback Tunnel, Finishes Package Washington Dulles International Airport. Presentation. Pete Dahl Construction Management. Senior Thesis, Spring 2004 Penn State University. - PowerPoint PPT PresentationTRANSCRIPT
Pedestrian Walkback Tunnel, Finishes Package
Washington Dulles International Airport
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Pedestrian Walkback Tunnel, Finishes Package
Introduction
Project Background
Breadth Study: Soil Retention System
Breadth Study: Curtain Wall System
Depth Study: Airport Project Delivery
Conclusions
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Intended Use:“Allow passengers the choice of a short walk between the Main Terminal and Concourse B, or transport via Mobile Lounge”
About the Project…
Key Issues:
1) Two levels below grade, Tunnel and Basement Level, 60,000 CY of bedrock to be removed from the site
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Key Issues:
2) Entire North Face of façade is glazed curtain wall
3) Pedestrian Walkback Tunnel Project is split up into 4 separate “packages”
About the Project…
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Tunnel Shell, Connector A under separate contracts
Existing Conditions for the Finishes Package:
Project Design
Finishes in the Tunnel to recall the swooping roof of the main terminal
Rendering of Tunnel:
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Owner: Metropolitan Washington Airports Authority (MWAA)
Owner’s Representative: Parsons Management Consultant (PMC)
Design Consultant: PMC Design
Project Team
General Contractor: Hensel Phelps Construction Co. (HPCC)
Major Subcontractors:
Soil Retention System: Berkel & Co. Contractors
Rock Grinding: J.H. Becker Co.
Earth Removal: Strittmatter Contracting, LLC
Engineer: Earth Tech
Architect: Giuliani Associates
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Project Organization
OwnerMetropolitan Washington Airport Authority
General ContractorHensel Phelps Construction Company
Owner’s RepresentativeParsons Management Consultant
EngineerEarth Tech
Subcontractors
Design ConsultantPMC Design
ArchitectGiuliani Associates
Fee-Based Contract
Fee-Based Contract
Lump Sum Contract
Lump Sum Contract
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Project ExecutionProjects are broken into phases, or “Packages”, in this case…
Combined to form “Finishes Package”
Tunnel ShellConnector AConnector B, Tunnel Interior FinishesAPM Tunnel
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Project Site
Existing Concourse B
Existing Main Concourse
Connector A (NIC)
Connector B
Tunnel Shell (NIC)
“Portal” (Tunnel Entrance) “Object Free Zone”
ACTIVETAXIWAY
ACTIVETAXIWAY
Tunnel Finishes
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Project Cost
For the Finishes Package alone…
Cost: approx. $25,000,000
Size: Connector B: Four Stories – 20,000 SF
Tunnel: 750 ft long x 30 ft wide – approx. 22,500 SF
Schedule: October 2002 – December 2004
For the Pedestrian Walkback Tunnel project…
Cost: $50,000,000
Schedule: Spring 1998, Design began
December 2004, expected completion
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Project Timeline
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Construction Process
• Drill and place tiebacks
• Spray 1st layer of shotcrete
• Tighten and test tiebacks
• Spray 2nd layer of shotcrete
• Rock Grinder grinds rock in 7’ lifts
• Spoils excavated with Excavator in 7’ lifts
7 repetitions to reach an overall depth of 44’
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Original Design8” Shotcrete wall with tiebacks on a 7’ x 7’ grid
4” Shotcrete w/ WWF
Constraints/IssuesNo setback allowed
Highly fractured, weathered rock
Poor RQD
Heavy surcharge loads
Existing Concourse B adjacent to site
Install Tiebacks
4” Shotcrete w/ WWF
Waterproofing with foundations
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
System AnalysisPost-Construction
Extremely weathered rock
Frequent minor collapses
Additional shotcrete
Groundwater issue
Sump pumps, temp. plumbing
Holding tanks
Carbon filtration process, fuel spill
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Alternate System SelectionSuggested systems, from geotech report:
Braced Walls using Wales and Struts
Soldier Beams & Lagging
Braced Sheeting
Bored-Pile Walls
Diaphragm/Slurry Wall
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Alternate System SelectionDiaphragm/Slurry Wall
Major Issue: Rocky subgrade conditions
Solution: The Big Dig in Boston, MA:
Similar soil conditions
Hydromills/Rock Mills
Clamshell bucket removes spoils
Image courtesy of www.bigdig.com
Excavate the Trench
Fill Trench with Slurry
Place Rebar Cage
Pump Concrete… …While Removing Slurry
Fill in all Adjacent Panels
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Alternate System Design
Using the same design conditions for the shotcrete & tiebacks
• Terzaghi and Peck Trapezoidal Apparent Earth Pressure Diagram, as recommended by the Geotech
GRADE
BOTTOM OF EXCAVATION44
’
Designed a beam with 1’ unit width to form a wall of multiple vertical beams
• 44’ Height of Excavation
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Alternate System DesignInput the 1’ width beam into STAAD
• Design reinforcing for the wall based on,
• STAAD results
• ACI
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Impacts on Sequencing
Old: CYCLE: Grind, Excavate, Shotcrete, Tiebacks, Shotcrete
New: Construct entire slurry wall before excavation begins
CYCLE: Grind, Excavate, Tiebacks
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Schedule Impacts
Old: 8 month duration, due to Differing Site Conditions
New: 3 weeks at front end for slurry wall
3-4 days per lift = 5-6 weeks total!
3 weeks
+ 5-6 weeks
8-9 weeks ~2 months!
~6 MONTH
DIFFERENCE
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Cost Impacts
Including,
• Rock Grinding: ~$400,000
• Excavation: ~$500,000
OLD SYSTEM:~$2,000,000
NEW SYSTEM:~$1,350,000
COST SAVINGS:
$650,000
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
ConclusionsEfficient use of slurry wall in most locations on the project
However,
Alternate system on South side at Concourse B, and at the Tunnel connection
Shotcrete problems vs. Slurry wall problems
The original shotcrete design is justified in its application
on this project.
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
OverviewPermanent building systems
• Greater impact on the building’s overall performance
Long-term owner, long-term building
• Improving quality will have lasting effects
• Security vs Energy Efficiency
• Life-cycle costs
Minor components, major impacts
Example: Curtain Wall System
-Glazing
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Modeling the original designCurtain Wall modeled into ENERGY10 software
• Double glazed system
• 1/4” glass with low-e coating
• 1/2” airspace
• 1/4” glass
• 2 layers of 1/8” sandwich a polyvinyl membrane
• improves soundproofing
• improves security
• U-value: 0.509 BTU/(hr-SF-F)
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Change impacts of various components
Value Engineering
Coatings:
• Low-e
Shading:
• Add shading system
Layers of Glazing:
• Triple glazing
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Cost Impacts
Low-e Coating Window Shading Triple Glazing
Annual Energy Use ~12% ~7% ~1%
Annual Energy Cost ~$570 ~$135 ~$50
Initial cost ~$3600 ~$7,000 ~$15,000
Rate of Return ~6.5 years ~50 years ~300 years
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
ConclusionsEvaluate the importance of Energy Efficiency with respect to…
• the actual application
• the initial cost
• the operating cost
The original glazing design holds the most value to the owner
in this application.
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Project EvaluationMajor elements of the design
• Retention System
• Structural System
• Building Enclosure
• Project Delivery?
Design of the Project Delivery Process…
• Affects: Pre-design through close-out
• Impacts:
• Level of coordination
• Methods of communication
• Overall project success
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Overview – A Project Delivery SystemProject Delivery Selection
• Owner Decision
• Impacts seen throughout the Pedestrian Walkback Tunnel project
Define impacts on Pedestrian Walkback Tunnel project
Analyze the impacts on other airport projects
Identify common tensions
Applicability to other market sectors…
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Project Delivery SelectionElements affecting the Project Delivery Process
Owner experience, capabilities
-e.g. Multiple projects for MWAA; construction staffing
Source of funding
-e.g. Public bonds for MWAA
Project complexity
-e.g. Tunnel Construction is unique
Project timeline
-e.g. Not urgent; compare to data center, pharmaceuticals
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
OwnerMetropolitan Washington Airport Authority
General ContractorHensel Phelps Construction Company
Owner’s RepresentativeParsons Management Consultant
EngineerEarth Tech
Subcontractors
Design ConsultantPMC Design
ArchitectGiuliani Associates
Fee-Based Contract
Fee-Based Contract
Lump Sum Contract
Lump Sum Contract
Contracted directly with the owner
The ‘Packaged’ Project Team
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
OwnerMWAA
General ContractorHPCC
Owner’s RepresentativesPMC, PMC Design
EngineerEarth Tech Design Team
General Contractor
Owner’s Representatives
Design Team
General Contractor
Owner’s RepresentativesFinishes Package
All Entities are Contracted Directly with the Owner
Tunnel Shell
Package
Connector A Package
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Dulles Airport
Pedestrian Walkback Tunnel
MWAA
Tunnel Shell
Connector A
Tunnel Finishes
Connector B
West APM Tunnel
OtherProjects
OtherProjects
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Commonalities to other Airport ProjectsData Collection
Survey
• Sent to airports across the country
• Gathering information from multiple airport projects
Results
• Four International Airports:
• Washington Dulles International Airport
• Baltimore Washington International Airport
• Miami International Airport
• Seattle-Tacoma International Airport
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Key questions:
How was the project awarded?
How was the project funded?
What type of contract was used?
What were the effects of phasing or packaging on the project?
Additional questions alluded to the relationship developed between project team members
-Corresponds to the number of change orders, schedule extensions and general communication
Commonalities to other Airport Projects
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Respondents:
Primarily contractors, an architect
Common Responses:
Use a contractor selection method based on Best Value
• Low Bid is insufficient
• Funding source not a barrier – eg. BWI
Use a lump sum contract
• If quantities are unknown, use Unit Price – eg. Excavation
Commonalities to other Airport Projects
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Responses cont.:
Packaging common throughout the Airport market sector
• Due to increased communication between packages
• As a result…significant cost growth
Phasing less common
• Less cost growth seen, as on BWI (NO cost growth)
• Better relationship between Owner’s Rep and GC
Commonalities to other Airport Projects
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
AnalysisA change is needed…
The first steps:
• Owner decisions related to Project Delivery have the ability to create, or relieve, tensions in the project team
• How does an owner know if a decision will negatively impact their project?
• More owners must be educated to understand impacts of their decisions
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Owner Education
Impact on the Project Possible Results
Low Bidder Highly competitive bidsChange orders are a major issue
Best Value
Contractors are encouraged to find the best way to deliver the project
Change orders are less frequent
Owner and contractor interests are more closely aligned
Help more owners to realize the impacts of…
• Contractor Selection Criteria
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Owner Education
Impact on the Project Possible Results
Lump Sum Highly competitive bidsChange orders more likely
Unit Price
Undefined quantity – owner pays for work performed, w/in scope
DSC change orders smaller due to predefined unit price
Less competitiveOwner gets what they pay for, good or bad
Help more owners to realize the impacts of…
• Type of Contracts
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Owner Education
Impact on the Project Possible Results
NoneEntire project is bid at one time
Lower bids due to economies of scale
Decrease in coordination required on project
Phasing
Entire project is bid at one time
Lower bids, decreased coordination
Phasing requirements define sequencing
Contractor understands/buys-in to owner’s interests in phasing
PackagingProject is bid out at different times in packages
Higher bids due to increased coordination, mobilization impacts
• Fast-Tracking the project
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
ConclusionsA fundamental change is needed.
Until then,
Owner education is key
Allowing for,
Decreased tensions
Better relationships within team
Less wasteful projects
Better product delivered to the owner
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Presentation SummaryAnalyzing the Pedestrian Walkback Tunnel,
• Soil Retention System Slurry Wall
• Significant issues eliminated
• Cost and schedule decreased
More importantly,
Analysis focuses around the owner’s needs and requirements and their definition of value
• Curtain Wall System
• Low-e, double glazed windows are optimal
• Project Delivery Systems Analysis
• Further education
• Increase awareness of the impacts of owner decisions
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
QUESTIONS?
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Impacts
Cost
Costs can be justified through the savings of time from the duration of the excavation, and also the redesign of formwork for the concrete foundation walls.
Old: SRS original cost: approx. $700,000
Change Orders: nearly $700,000
-DOUBLES the original cost of the system
-Due to Flooding and Earth Movement
New: 20,000 SF @ $10/SF = $200,000 for trench and slurry
2000 CY concrete, 1500 tons of rebar = $250,000
Rock Grinding: $400,000 (unchanged)
Excavation: $500,000 (unchanged)
Introduction
Project Background
Soil Retention System
Curtain Wall System
Airport Project Delivery
Conclusions
Dulles Pedestrian Walkback Tunnel, Finishes PackageWashington Dulles International Airport
Pete Dahl
Construction Management
Senior Thesis, Spring 2004
Penn State University
Impacts
Schedule
Old: 8 month duration 7 lifts ~ 1 month per lift
New: 3 weeks added at the front end of the project for slurry wall
-Mobilization: 1 week
-100 lf/day @ 400 lf = 4 days ~ 1 week
-Demobilization: 1 week
Better flow of work due to decreased activities on site
-2 rock grinders: 2 days
-Full use of loader and excavator
-Tiebacks installed in 2 days
3-4 days per lift = 5-6 weeks total!