arema 2015 1 · schedule would not be compromised: at any time during construction of the concrete...

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Figure 1: Concrete Casing During Construction in Winter 2014 (Photo Credit

STV, Inc.)

Amtrak’s Hudson Yards Concrete Casing Right-of-Way Preservation Project, New York, NY Author: Craig J. Rolwood, PE Formerly National Railroad Passenger Corporation (Amtrak), Retired Currently: Consultant Number of Words: 4015 ABSTRACT The National Railroad Passenger Corporation (Amtrak) undertook a $185 million project to construct an 825-foot long by 52-foot wide, 35-foot tall, reinforced concrete, double barrel underground structure, with an invert up to 65 feet below the existing ground surface, using cut-and-cover tunneling methodology. The project is called the Phase I Hudson Yards Concrete Casing ROW Preservation Project (Concrete Casing Phase I). The project’s purpose is to preserve the underground right-of-way for a potential future tunnel through an area undergoing real estate development. A future tunnel is needed to expand passenger rail capacity into New York City, the nation’s biggest metropolis and financial capital; to provide rail system resiliency in the event of future super-storm events such as was experienced during Hurricane Sandy; and to allow operational flexibility needed for major rehabilitation of the existing 100 year old Hudson River tunnel. Unusual features of the project work included fast track planning, legal agreements, environmental permitting, design and construction; support of overbuild platform and building loads on the concrete casing structure; heavy construction immediately adjacent to an active passenger rail tunnel and within an active railroad storage and maintenance yard facility; coordination with nearby development projects; agreements with Long Island Rail Road (LIRR) for demolishing and rebuilding their Maintenance of Equipment facility; and site construction access and logistics within a highly constrained, urban environment. PROJECT DESIGN DEVELOPMENT Amtrak and a Real Estate Developer Plans for Use of LIRR’s West Side Yard During 2010 – 2012, as part of its on-going planning process for the future of the railroad, Amtrak performed high level conceptual evaluations of the technical feasibility of adding two new tracks under the Hudson River and of tying these new tracks into the existing Amtrak Penn Station complex, going through the West Side storage and maintenance yard owned by the Metropolitan Transportation Authority (MTA) and its subsidiary, Long Island Rail Road (LIRR). During the same time, Related Companies, a real estate development corporation, under agreement with MTA/ LIRR, advanced plans to provide an overbuild development of LIRR’s West Side storage and maintenance yard (Overbuild Project). The Overbuild Project involves the Related Companies constructing a platform above the Eastern Rail Yard Section and the Western Rail Yard Section of the LIRR John D. Caemmerer West Side Yard that will provide the foundation for commercial and residential development with buildings as tall as 1,250 feet above the ground surface.

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Figure 2: Planned Hudson Yards Mega-Development (Image Credit Related Cos.)

During 2012, it became apparent that construction of part of the Overbuild Project in the eastern half of the rail yard could likely start soon. This development threatened to enjoin the use of the area below as a right-of-way for new trans-Hudson tunnels to access Penn Station. Concept Development To preserve the right-of-way for a future tunnel, Amtrak would need to design and build an underground structure in coordination with the Overbuild Project – a figurative “down payment” for the future of passenger rail access to Manhattan from the west. This underground structure would be located between 10th Avenue and 11th Avenue, and 31st Street and 33rd Street below the proposed Related Companies’ Hudson Yards development Overbuild Project. In discussions among Amtrak, LIRR, Related and contractor Tutor-Perini Corporation, Amtrak authorized a “Four-Week Study” in October 2012 to determine if and how Amtrak’s need for an underground right-of-way could be accommodated within Related’s plans for its Overbuild Project. As a result of that study, it was determined that it was technically feasible to provide for Amtrak right-of-way preservation by construction of a cut-and-cover, reinforced concrete casing underground structure that would be closely coordinated with the design and construction of the Overbuild Project. Superstorm Sandy At the same time as the Four-Week Study was underway, Superstorm Sandy hit New York City on October 29, 2012. Amtrak suffered extensive damage to portions of its Northeast Corridor (NEC) transportation infrastructure, particularly the infrastructure in and around New York City and northern New Jersey. Superstorm Sandy led to significant damage to Amtrak’s existing Hudson River tunnels, resulting in the cessation of all Amtrak NEC intercity passenger rail and New Jersey Transit service into New York City for several days, affecting thousands of daily riders and causing substantial economic harm. This event highlighted the need for improvements of vital elements to harden the existing tunnel system from future such emergencies and to create redundant capacity into Penn Station, the nation’s busiest rail terminal. Superstorm Sandy exposed the risks of solely relying on a system of two single-track 100-year-old tunnels for rail access into New York City. Procuring Design Services It was determined that construction of the Overbuild Project could begin as early as mid-2013. Because of the tight schedule, Amtrak quickly developed a scope of services for designing the concrete casing

Figure 3: West Side Yard Flooding During Superstorm Sandy (Photo Credit: LIRR)

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needed to preserve the right-of-way in the eastern portion of the LIRR rail yard. Amtrak had begun advertising for design services even before completion of the Four-Week Study. Amtrak employed a two-step process of pre-qualifying designers and then receiving and evaluating technical and price proposals from pre-qualified firms. Amtrak procured the professional design services of a tri-venture team, The Gateway Trans-Hudson Partnership, consisting of Parsons Brinckerhoff, AECOM, Inc. and STV, Inc., and was able to provide Notice to Proceed by early January 2013. Design progressed rapidly over the next number of months. Biweekly design progress meetings, biweekly design technical meetings, and additional technical workshops that included the various project stakeholders were held throughout the design process. The design was substantially complete by June of 2013, and was fully completed with all stakeholder input incorporated, by August of 2013. Environmental Constraints and Documentation

Figure 4: Environmental Action Components from EA Documentation

Amtrak worked with its federal oversight agency, the Federal Railroad Administration (FRA) to establish what National Environmental Policy Act (NEPA) documentation would be required for the project. It was determined that, if the project purpose and need was limited to the preservation of the right-of-way so as not to preclude the potential for a future rail tunnel, then an environmental assessment could be prepared and a Finding of No Significant Impact (FONSI) might be obtained. Amtrak needed to be careful to assure that a piecemeal, “segmentation” approach to environmental evaluation was not being done, because ultimately a full environmental impact statement would be required for the future, full, extensive cross-river tunnel and infrastructure improvements.

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Figure 5: Phase I Concrete Casing Midway Through Construction

Through pre-existing task order contracts, Amtrak competitively procured the services of URS to prepare the Environmental Assessment, in close coordination with Amtrak’s designer. Working with FRA and project stakeholders, a FONSI for the project was obtained in May 2013. FUNDING In April of 2013, Amtrak submitted an application to the FRA to fund the first phase of the Hudson Yards Concrete Encasement project under the Disaster Relief Appropriations Act of 2013. In recognizing the need for a new tunnel structure designed to withstand future storm surge and other weather events, the Federal Transit Administration (FTA) on June 19, 2013 transferred $185,000,000 to the FRA to provide funding to Amtrak for the construction of the initial phase of the Hudson Yards Concrete Encasement project (Hudson Yards Phase I). FRA awarded these funds to Amtrak on June 20, 2013. While the bulk of the funding covered anticipated contractor construction costs, many millions of dollars were included for construction management, third party review, payments for loss of use of the LIRR Maintenance of Equipment Building, and sundry oversight, management and administrative costs. STAKEHOLDERS AND LEGAL AGREEMENTS A Complex Legal Coordination Parallel with and crucial to the work of the project were legal and business negotiations of rights and responsibilities among the stakeholders. The main stakeholders included MTA, owner of the property; LIRR, MTA’s subsidiary that operated the rail yard and maintenance of equipment building within the yard; Related Cos., the developer that was already in agreement with MTA for rights to overbuild the yard; Tutor-Perini Corporation, the contractor already working with Related towards a major agreement to perform the construction of the Overbuild Project; and Amtrak. Other stakeholders included the City of New York (street usage during construction); utilities such as ConEd; and New York City Transit Authority, who was constructing an extension to the No. 7 subway nearby. The types of agreements required included an easement for Amtrak to allow for its underground structure; agreements for coordination efforts during construction of the projects; agreements for design and construction services; and agreements for compensation and/or cost sharing for direct and indirect impacts, and potential savings, caused by construction of the concrete casing. Long Island Rail Road All the work would be performed within the LIRR yards. It was determined early on that the section of the yard where the concrete casing would be constructed would be isolated from yard operations and placed under the contractor’s site responsibility. Maintenance of Equipment Building One of the most difficult agreement, schedule and coordination aspects of the project involved LIRR’s active Maintenance of Equipment Building. As part of Related’s Overbuild Project, the developer had already planned to partially demolish some office and administrative functional areas of the building to accommodate its construction; but it had developed some tentative, complex plans for installing its

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overbuild supports while maintaining rail access to the building and maintaining daytime equipment servicing operations in the building. Amtrak’s concrete casing project would require removal of additional portions of the building but especially rail access, such that the building could not function during construction. LIRR would need to perform the building functions at another location during the period of disruption caused by construction. The costs to relocate its unionized workforce, to shuttle trains, and other incidentals would need to be reimbursed to LIRR by Amtrak. An agreement for this was made, which included the need-by date for return of the building. Once it was decided that the Maintenance of Equipment Building would be partially demolished, Related and LIRR created a new arrangement between themselves, developing a plan to demolish a much greater portion of the building and rebuild it on an expanded footprint, permanently relocating some of the rail yard functions to this building (in particular, the yard control center). This arrangement apparently provided mutual benefit to LIRR and Related. The determination of a fair cost allocation for demolition, redesign and reconstruction efforts between Related, LIRR and Amtrak increased in complexity. The Developer, Related Cos. The placement of immense support structures throughout the Eastern Rail Yard Section for the Overbuild Project platform started in 2013. Related retained the theoretical right to assure that its Overbuild Project schedule would not be compromised: at any time during construction of the concrete casing, if the casing construction would negatively impact the overbuild construction, Related could initiate the exercise of its rights to assure the timely execution of the overbuild project work. Support of Overbuild Foundations on Amtrak’s Concrete Casing During the design coordination among stakeholders, one of the major, complex features involved designing the concrete casing to support the Overbuild Project foundations. The Gateway Trans-Hudson Partnership, Amtrak’s designers, coordinated extensively with Related’s building design consultants to establish the location of foundation supports and their loadings. This was especially challenging because the overbuild designs were continuously changing and less developed than the concrete casing design. The overbuild foundation support requirements fell generally into three areas. The first area was support of a planned retail commercial building above the eastern, 10th Avenue section of the concrete casing. Design foundation column loads in this retail building area were up to 6000 kips. The second support area was a large expanse of platform-only columns, where a large open plaza was planned for the Overbuild Project. Design foundation column loads on this second area were generally 1000 to 2000 kips. At the very western end, abutting 11th Avenue, the concrete casing would need to support the north face of a high rise, planned residential tower. This “Tower D” building design was least developed of all designs; conservative assumptions for multiple foundation loads of 16,000 kips each in imprecise

Figure 6: LIRR Before Construction

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locations resulted in massive floors, walls, roofs and deep support beams above the casing roof, to accommodate the Tower D loads. Besides the actual design of the concrete casing for these support loads, there were important quality and regulatory considerations to address. Accurate and future-accessible documentation of permissible loads and load distribution needed to be made. Assurance to NYC Building Code enforcers of the quality construction of the casing that would serve as foundation support of portions of the overbuild was also required.

The Contractor, Tutor-Perini Corporation Because of the very constrained site and massive construction coordination efforts anticipated, it was decided early on that the only practical approach to constructing the Amtrak concrete casing and the Overbuild Project concurrently would be to have the same contractor responsible for both. Therefore, Amtrak entered into agreement with Tutor-Perini Corporation, procured on a single source basis, to construct the concrete casing. Two atypical things were done as part of this agreement: assignment of the underway design contract to create a design-build arrangement, and using open-book methodology to establish the agreed construction price. Assignment of the Design Contract Amtrak’s legal department determined that rolling the existing design contract into the contractor’s agreement, thereby creating a design/build arrangement, was desirable for effective risk management and establishment of lines of responsibility. Even with this arrangement, during construction, some of the

Figure 7: Typical Cross Section Sketch of Two Barrel Concrete Casing and Excavation

GROUND SURFACE

SUPPORT OF EXCAVATION (SOE)

ROCK BOLTS

TWO BARREL CONCRETE CASING

ROCK

PEDESTAL SUPPORT FOR OVERBUILD

SOE TIEBACKWATERPROOFING

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quality control and assurance procedures were questioned, because there were various stakeholders with their own, individual concerns. Establishing Construction Price Using Open-Book Methodology Because the construction contract would be single-sourced and not competitively bid, an “open book” method of pre-construction, estimated cost verification was used to establish a “fair and reasonable price”. The open book method means that the contractor shows all his assumptions and calculations regarding labor rates, productivity, material quantities, equipment usage, back-office support, and all other incidental costs in detail. Amtrak engaged a third party contractor experienced in the New York City heavy construction market to independently review and verify cost estimate prepared by Tutor-Perini. Multiple, open meetings were held, some exclusively between the contractor detail estimators, and many opened to include the contractors, Amtrak, the developer, the designer’s estimators and the funding agency, FRA. Through the open book method, agreement was reached on price and schedule of values to pay the contractor. CONSTRUCTION Maintenance of Equipment Building Demolition LIRR vacated the Maintenance of Equipment Building beginning August 2013. Construction notice to proceed was issued to the contractor in August 2013. One of the first items of business, after some preliminary utilities work was addressed, was demolition of the building, which was accomplished in very short order. Building demolition included storage and protection of some high value shop equipment that was designated for reinstallation and continued use in the reconstructed building. Building lead tracks were removed and rail, including turnouts/switches, stored. Yard Utilities While public utility involvement was minor for this project, many near surface LIRR yard utilities were affected by construction and required temporary and/or permanent rerouting. These utilities included gas service; electric lighting; DC electric feed for the railroad third rail traction power systems; a large, storm sewer gravity and force main system; and other utilities. Support of Excavation and Soil Excavation Rock level varied throughout the site but was generally 20 to 30 feet below the surface. The full depth of excavation varied from 30 feet deep at the east end to 65 feet deep at the west end. The Contractor used secant pile walls consisting of interlocking, 2 ½ or 3-foot diameter steel and concrete filled casings, to provide soil support during excavation. Tiebacks and walers were employed for wall support to avoid the access obstruction that cross-cut struts would cause. Soils were excavated in a controlled sequence using standard earth moving equipment. Trucking excavated materials away from the site required careful planning and scheduling, which was a common challenge for all site operations on the constrained site that emptied out onto busy Manhattan thoroughfares.

Figure 8: Typical Support of Excavation

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Figure 9: Rock Excavation Immediately Beside Empire Tunnel

The soils were environmentally categorized as urban industrial, typically found in the highly developed and redeveloped sites of Manhattan. No major site clean up was required, though LIRR did have Amtrak remove and replace an underground oil separation tank that did not meet current code requirements. Rock Excavation and Mass Grouting Rock quality varied some but not greatly through the site. The bedrock generally consisted of Manhattan Schist, with some quartz. Rock was harder towards the west end than at the east end of the excavation. The Contractor performed some mass rock grouting to seal points of water infiltration through fissures within the rock, and thus provide for a dryer excavation site. The need for mass rock grouting was limited to a few areas. Note that as part of the secant pile wall installation, jet grouting was used to also provide sealing against water infiltration. The Contractor intended to remove much of the rock through controlled blasting. While preparing detailed blasting plans, the Contractor began manually removing rock using ram hoes. As the multiple approval processes and review times for blasting plan approvals lengthened, the Contractor eventually opted to continue with the steady, manual removal process, which worked well at this site except for a few local areas of quartz and where the Schist become quite hard towards the west end. Two small issues arose during rock excavation. First, the constant noise from the manual rock removal became a community issue from residents in a nearby apartment building; the contractor agreed to limit its hours of rock excavation. Second, the noises from the pounding traveled through the rock and made sounds within New York City Transit Authority’s No. 7 Line construction tunnel, and this confused and concerned some workers and managers. Proximity of Amtrak’s Empire Line Tunnel During design, a careful survey was made to check the alignment of Amtrak’s Empire Line tunnel vis-a-vis the proposed, new concrete casing. Amtrak has a shallow, one-track tunnel that was constructed in the 1980s and runs below the surface of the LIRR rail yards. It was determined during design that the excavation for the concrete casing would come within six inches to two feet from the Empire Line Tunnel at its closest point. Careful analysis was made to assure that the tunnel would be sufficiently weighted and secured to prevent possible shifting during construction. Reinforced Concrete Casing Construction Two layers of reinforcing steel were placed in all the floors, walls and roofs. Generally, #11 bars at close spacing are used to help carry the massive loads of not only the concrete casing and soils around, but also of the variable overbuild loads supported by the casing. Concrete placements of up to ten feet thick were made. Mass concrete construction includes provisions to control temperature rises and differentials within the mass concrete poured. Temperature monitoring was incorporated at thicker floor and roof, per specifications. Some temperature control methods included limiting cement ratios and use of admixtures to control curing rates; mixing ice during hot weather; provision of surface curing period insulation to control surface-to-interior differentials.

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The concrete roof was formed using a sophisticated system involving a movable, height adjustable, scaffold formwork. Waterproofing, consisting of a solid membrane system, was installed on shotcrete-smoothed surfaces prior to placing reinforcement and placing the concrete. A major challenge with waterproofing is protecting it against tears and rips during delivery and manipulation of rebar, formwork and placing concrete. Backfill and Overbuild Construction Almost as soon as the site was backfilled, even before final utilities were placed, erection of the Maintenance of Equipment building columns and overbuild steel above the tunnel began. The concrete casing is hidden from above ground observation. There are a few personnel shafts with ladders and stairs that allow access into the interior of the casing, expected to serve until the time that the casing gets incorporated into the continuous, new railroad tunnel beneath the Hudson River that will connect NY’s Penn Station with New Jersey and westward. Restoration and Expansion of Maintenance of Equipment Building As of June 2015, the Maintenance of Equipment Building is being reconstructed in its new, expanded form. Site utilities in the building and the nearby yard are being installed. Trackwork has begun to be reinstalled. ON-GOING AND FUTURE ROW PRESERVATION Current Status (as of June 2015) As early as October, 2013, Amtrak commenced the planning of Phase II to facilitate future construction phasing of needed extensions to the concrete casing for more right-of-way preservation. The first step of the second phase of the work is to extend the concrete casing by 105 feet beneath NYC’s 11th Avenue Viaduct. This has been designed and is under construction during 2015. Phase II has many of the same challenges as Phase I, and additionally includes maintaining 11th Avenue traffic while demolishing an existing bridge pier and rebuilding it, and founding the rebuilt pier on the concrete casing. An additional 550 feet of concrete casing is being designed for the west rail yard portion of the LIRR rail yard, in anticipation that eventually the developer will overbuild that area, again requiring the coordination of proposed Amtrak construction and overbuild development. An added challenge to this piece of the work is the need to temporarily support an active NYC Park – the Highline, a converted rail viaduct that has become a popular, linear park. Amtrak has also begun partnering with sister agencies in the NY-NJ area to begin the process of planning for the new Hudson River tunnel crossing. One of the first steps is preparing an extensive Environmental Impacts Statement.

Figure 10: Waterproofing, Reinforcement, Concrete and Formwork

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Figure 11: Nearly Completed Casing Barrel Photo Credit: Amtrak Construction

ACKNOWLEDGEMENTS With a project with so many contributing individuals, the danger in naming them is that inevitably someone will be inadvertently omitted whose contributions were important. Amtrak’s Northeast Corridor Infrastructure and Investment Development – the “business” guys – were in overall responsible charge of the project orchestration and the stakeholder coordination. The effort was led by Bob LaCroix, Deputy Chief of Improvements, with support from Vice President Stephen Gardner. The grant application was prepared by Christine Suchy and Rory Beelek. Amtrak’s legal effort was spearheaded by Michael Collins. Diane Herndon oversaw the legal effort. Michael was ably assisted via contract by lawyers from the Venable LLP of New York City. Richard Gans and Roberta Pederson led LIRR’s management and legal effort. Amtrak procurement lead was Leonard Rotteveel. From Amtrak design engineering, author of this paper Craig Rolwood served as Project Manager. Deputy Chief Engineer of Structures Jim Richter supported the work of the engineering group, and Director of Design John Brun provided input at critical times. From Amtrak construction engineering, Project Manager Clavel Crump led the construction management effort, supported by Deputy Chief Engineer of Construction Joe Rago, and ably assisted by Amtrak internal staff and contract help from the LiRO Group. The environmental documentation effort, prepared by URS under primary guidance from the Amtrak engineering department, was reviewed by many including Craig Caldwell of Amtrak and Gordon Johnson of LIRR. John Coulter as LIRR Chief Engineer, succeeded by Lori Katzman, provided leadership of the LIRR project effort. George Ehrhardt and George Asimenious were the point guys who did any and everything when it involved the LIRR West Side Yard. The Gateway Trans-Hudson Partnership design team for Phase I was ably led by Irfan Oncu, Chris Bennett and Drew Bazil. Tutor Perini’s team was led by Jeff Brown and Henry Cheung from the executive level. Timothy Dickson was project engineer, and Scott Tankel was construction Project Manager. The Tutor team was rich with contributing individuals, both construction specialists and generalists. LIST OF FIGURES Figure 1: Concrete Casing During Construction in Winter 2014 (Photo Credit STV, Inc.) Figure 2: Planned Hudson Yards Mega-Development (Image Credit Related Cos.) Figure 3: West Side Yard Flooding During Figure 4: Environmental Action Components from EA Documentation Figure 5: Phase I Concrete Casing Midway Through Construction Figure 6: LIRR Before Construction Figure 7: Typical Cross Section Sketch of Two Barrel Concrete Casing and Excavation

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Figure 8: Typical Support of Excavation Figure 9: Rock Excavation Immediately Beside Empire Tunnel Figure 10: Waterproofing, Reinforcement, Concrete and Formwork Figure 11: Nearly Completed Casing Barrel

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A R E M A 2 0 1 5 A N N U A L C O N F E R E N C E

Minneapolis, MN | October 4-7, 2015

Amtrak and West Side Development

Planned Mega-Development (Image Credit: Related Cos.)

Amtrak Future Tunnel Plans



Amtrak and West Side Development

Amtrak Future Tunnel Plans - Manhattan

Hudson Yards Development in West Side Yard



Four Week Study

Two-Barrel Concrete Casing

• Designer and Contractor

• Questions

– “Not to Preclude”?

– Can a tunnel and overbuild project be built together?

– Cost $$$ ?

– Schedule ?

• Result

– Concrete Casing Built in Coordination with Overbuild, Supporting Loads



Superstorm Sandy

Storm Night at West Side Yard (Photo Credit: Long Island Rail Road)

Site Flooding(Image Credit: Long Island Rail Road)

West Side Yard



Design Services

Planned Overbuild Development (Image Credit: Related Cos.)

Design: Fit Future Tunnel and Schedule with Overbuild Construction

Critical 2013‐2014 Construction

West Side Yard



Environmental Documentation

• ROW Preservation – Not Segmentation

• Casing Pathway (Blue)

• Maintenance of Equipment Building (Brown)

• Lead and Yard Tracks (Yellow)

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Funding



Legal AgreementsSTAKEHOLDERS

• MTA/Long Island Rail Road

• Related Cos.

• Tutor Perini

• Amtrak

SERVICE PROVIDERS

• GTHP – Design Team

• Contract Legal

• Contract Environmental

• Contract Pricing Review

• Real Estate Market Advisor



Maintenance of Equipment Building

MoE Building in Yard

• Major Issue

• Costly to Relocate Operations

• LIRR Union Labor Agreements

• Monthly Compensation

• Need Back in Service Late 2015

RampMoE Demo

Planned Casing

Lead Tracks



Support of Overbuild Foundations

Pedestals and Access Hatch(Photo Credit: Amtrak Construction)

Two-Barrel Concrete Casing

Support Pedestal On Casing Roof



Design Build & Open Book Pricing• Federal Acquisition

Rules

• Single-Source Justification

• Open Book Negotiations

• Expert Reviewers



Construction – MoE Demolition

Remaining MoE Building FrameMoE Building Demolition(Photos Credit: Amtrak Construction)

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Construction - Yard Utilities

Storm Force Main Relocation (Photo Credit: Amtrak Construction)

• Permanent and Temporary Relocations Required

• Included:

– Storm Drainage

– Site Electric

– RR DC Electric

– Sanitary

– Gas

– Fire Protection



Soil Excavation and Support

• Secant Piling Wall

– Relatively Unyielding

– Water Barrier

– High Strength

Typical Secant Pile Wall Section



Soil Excavation and Support

(Photos Credit: Amtrak Construction)



Rock Excavation

Mass Rock GroutingRock Ex and Rock Bolts(Photos Credit: Amtrak Construction)



Proximity of Empire Line Tunnel

Empire Line Tunnel Monitoring

Empire Line Tunnel at Shallow depth

Excavation Besides Empire Tunnel




Casing Construction - Preparation

Shotcrete and Waterproofing Mud Mats


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Casing Construction - Resteel

Reinforcement Steel Bending and Placement(Photos Credit: Amtrak Construction)



Casing Construction - Formwork

Formwork Installation(Photos Credit: Amtrak Construction)



Casing Construction - Concrete

Concrete Delivery and Placement(Photos Credit: Amtrak Construction)



Casing Construction – Backfill, Overbuild

Overbuild in 2015(Photos Credit: Amtrak Construction)

Backfill Operations



Some Lessons Learned

Concrete Casing Interior(Photo Credit: Amtrak Construction)

• Contractual– Interests to Satisfy

– Schedule Paramount

– NYC Construction

• Technical– Water Seepage

– Rock Excavation – Manual vs. Blasting



Future Plans

Phase 2: Amtrak FutureROW Preservation Needs

Phase 1

Phase 2

Hudson Yards Site

arema 2015 1 · schedule would not be compromised: at any time during construction of the concrete...

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