Location: New York, NY
Owner: New York State Department of Transportation
Contractors: China Construction America, Inc./Halmar International, LLC JV

Siefert Associates, LLC designed a temporary structure for ramps 6A and 7A. In addition, we provided construction engineering for substructure and lateral support, jacking plans and crane demolition and erection plans. The erection of Ramp 6A was successfully completed in May 2012 and the demolition plan for the removal of Temporary Ramp 7A was submitted for construction.

Location: Staten Island, NY and Bayonne, NJ
Owner: The Port Authority of New York and New Jersey
Contractors: Skanska Koch-Kiewit, JV

As the fourth largest arch bridge in the world, the Bayonne Bridge connects Bayonne, New Jersey and Staten Island, New York, spanning over the entrance to the Port Newark-Elizabeth Marine Terminal.  The height of ships serving the port was limited by the Bayonne Bridge. This limitation grew more serious with the Panama Canal's 2016 expansion that enabled bigger, New Panamax ships to reach the port from Asia. The Port Authority of NY&NJ awarded the contract to raise the Bayonne Bridge's roadway 65 feet at a cost of around $1.7 billion. The increased navigational clearance to the busiest port on the East Coast was achieved in June 2017, and the overall bridge project was completed in 2019.

Siefert developed a comprehensive strategy for the temporary works including Temporary Supports and Pile Foundations, Engineered Lift Plans for Demolition and Erection of the Main and Approach Spans, Rigging Design, with related Structural and Geotechnical Analysis. The engineered solutions minimized disruptions to the navigational channel below and to the roadway traffic, while maintaining stability of the existing truss arch.

Piers for the new viaduct approach spans had to be constructed directly through the existing roadway, which required selective demolition of the existing structure and pier bents. Temporary shoring towers were engineered to maintain the traffic flow and preserve the structural integrity of the bridge. Weak subsurface soil conditions warranted the design of deep micro-pile foundations with concrete pier caps.

There were 2 different types of temporary support towers designed, a heavy duty tower that supported the 10 feet deep edge girders and a light duty tower that supported the 6 feet deep floor beams. The towers had to be designed to support 2 lanes of live load traffic [HS-20, 36 tons each] and the segment haulers [600 tons] used to transport the precast pier segments across the bridge. Unique solutions were developed by Siefert to take advantage of the existing framing and to save the contractor time and money.

Siefert Associates meticulously formulated, evaluated, and provided detailed lift plans for the removal and replacement of all bridge components. These lift plans entailed extensive dimensional assessments to ensure that cranes with complicated rigging had ample clearance to safely lift and lower loads from the roadway to their final positions. Our teams assumed the responsibility of conducting a comprehensive analysis of the structural capacity of members and connections during all construction phases. This analysis was imperative to confirm the ability of the bridge deck and superstructure to support the substantial loads from cranes, heavy haul transporters, and excavators, all within the existing structure configuration at the time of the operation. Also, a geotechnical analysis was performed and working platforms and temporary roadways were designed for equipment operating on grade below and adjacent to the structure.

Location: Newtown, CT
Owner: State of Connecticut
Contractors: Empire Paving Inc.

An emergency culvert repair project on Mile Hill Road [Route 860] in Newtown, CT quickly transformed into emergency culvert replacement due to the discovery of severe deterioration of the existing culvert pipe. Siefert Associates, LLC supported the deep excavation by designing a combination of temporary support of excavation (SOE) systems, such as GRES walls, braced soldier piles and lagging systems and soil nail walls. Additionally, the project scope included the design of a cantilevered reinforced concrete headwall and endwall, modified to accommodate right-of-way restrictions, and stabilization of existing subgrade soils.

Location: Boston, MA
Owner: Massachusetts Bay Transportation Authority [MBTA]
Contractors: GLX Constructors

In support of the extension of Boston’s oldest rapid transit line, Siefert Associates, LLC provided engineered lift plans for several rebar cages and designed the lifting rings to maintain the geometry of the cage. We also collaborated with the contractor on the design of formwork and falsework for the pier caps and columns, providing a third party review of the contractor’s where necessary, and designed temporary utility supports for several bridges within the 4.7-mile project limits.

Location: Boston, MA
Owner: Massachusetts Department of Transportation
Contractors: Atlantic Coast Dismantling, LLC

To facilitate the safe demolition of this bridge, Siefert Associates, LLC was hired to perform bridge demolition analysis and prepare engineered lift plans. SALLC analyzed the existing superstructure for construction equipment loading, analyzed the staged removal of sections of the main span truss, and designed temporary bracing of the main span truss and approach span girders. The steel truss mainspan and most of the approach spans were removed with a large crane on a barge.

Location: New York, NY
Owner: Triborough Bridge & Tunnel Authority
Contractors: Restani Construction Corporation

Due to corrosion in the concrete foundations, the Manhattan approach of the bridge needed to be replaced. Siefert Associates, LLC was hired to design an extensive temporary shoring system, up to thirty [30] towers in total, to support the two-level viaduct structure and five [5] lanes of traffic on the bridge during all phases of construction. Extensive SOE designs were also needed to facilitate footing removal to bedrock without interrupting adjacent traffic.

Location: Waterbury, CT
Owner: Connecticut Department of Transportation
Contractors: I-84 Constructors JV

Siefert Associates, LLC was involved in several scopes of work, mainly focusing on the demolition and/or lift plans for the eight highway bridges that were constructed or replaced. The lift plans included rigging design, analysis of temporary supports and bracing as needed, and concise procedures for steel erection and jacking. SALLC also provided geotechnical services for various sites within the project limits, designing geosynthetic reinforced earth system [GRES] walls at the bridge abutments and producing temporary support of excavation [SOE] designs for several bridge foundations, retaining walls, and culverts.

Location: Boston, MA
Owner: Massachusetts Bay Transportation Authority
Contractors: SPS New England, Inc.

At 110-years-old, this structure needed to be strengthened, while preserving the historic façade, to accommodate the future increase in train frequency. Siefert Associates, LLC prepared engineered lift plans to carefully demolish the concrete walkways, parapets, and banding along the 1700-foot bridge with a combination of cranes on barges, cranes on grade, excavators on the superstructure, and hand demolition. Our team also created erection plans for the new floor beams, stringers, and deck panels, and designed shoring posts and a jacking procedure for the repair of girder seats of the bascule span.

Location: Brooklyn and Queens, NY
Owner: New York State Department of Transportation
Contractors: Granite Construction, Inc.

Siefert Associates, LLC was hired to prepare engineered lift plans for the spliced rebar cages of the piers of this bridge replacement, also designing the lifting rings and internal bracing to maintain the cage geometry. We also designed several overhang brackets on the exterior girders of the spans to support personnel, formwork, and concrete. A unique challenge was presented by the guide pipes of the cables, which prompted the design of a specialized overhang bracket to avoid interferences.

Location: Bronx and Queens, New York
Owner: New York State Department of Transportation
Contractors: Skanska Koch, Inc. & Judlau-OHL Group

During an earlier rehabilitation project, Siefert Associates, LLC provided inspection services and engineered designs for temporary construction; designing a horizontal, modular lifeline system and an air compressor platform for use by the contractor during repairs. The most recent rehabilitation consisted of a deck replacement along the full 2,190ft of the bridge, for which SALLC provided designs for the support steel and erection procedure for the 30T overhead gantry cranes, demolition and erection drawings for the main span, tower spans, and anchor spans, the design of temporary supports, platforms, and jacking brackets.

Location: Manhattan, NY
Owner: New York City Department of Transportation
Contractors: GCCOM Construction Company Inc.

Due to site constraints, the two trusses were assembled on a barge in the Hudson River, then lifted by a barge crane onto self-propelled modular transporters, which delivered the spans to a temporary staging location, and a hydraulic crane lifted them into their final position. Siefert Associates, LLC created the lift plans for the initial assembly and final erection of each truss span, as well as the erection of the access stairways at each terminus of the bridge. The team also analyzed the stability of each truss span on-the-hook and in its final position, and provided the contractor with comprehensive drawings depicting the procedure to pre-tension the truss rods.

Location: New York, New York

Owner: The Port Authority of New York and New Jersey

Contractors: American Architectural, Atlantic Hoisting & Scaffolding, DCM Erectors, EE Cruz, Gramercy Group, Granite Construction, Navillus Contracting, O’Kane Electrical, Peri Formwork Systems, Phoenix Construction, Skanska, Tutor Perini Corporation, and Yonkers Contracting Company, Winco Corporation/Sorbara Construction Corporation

Siefert Associates, LLC worked on numerous scopes since 200, including demolition and erection plans, analysis of slurry walls, design of temporary support, crane platforms, and protective shields, analysis of existing structure under construction equipment loading, design of temporary retaining walls and dunnage analysis. Notably, SALLC designed the trestle bridge, locally dubbed “The Siefert Bridge”, which created crane access for the installation of the memorial slab.