Bridges

Bridge analysis and design account for a significant portion of our portfolio. The firm has participated in numerous rehabilitation and new design projects. Our experience encompasses the entire spectrum of bridge engineering from small, single span, bridges and culverts to long span trusses and suspended bridges. LGM’s key personnel have performed structural analysis and design of all bridge types, including highway, movable, steel curved, truss, pre-stressed concrete, and suspension bridges.

We have an abundance of experience in conceptual through final phases of bridge design, bridge repair and rehabilitation, bridge replacement and widening, bridge seismic analysis and retrofit, construction support services, bridge inspection and condition evaluation. LGM has been actively involved in rehabilitation design of many long span bridges.

Our notable projects include:

George Washington Bridge
Bronx Whitestone Bridge
Throgs Neck Bridge
Brooklyn Bridge
Henry Hudson Bridge
RFK (Triborough) Bridge

SERVICES

Bridge rehabilitation, repair and widening
Design of new bridges and transportation structures
Seismic analysis, vulnerability assessment and seismic retrofit
Load rating analysis
Construction support services

Bridge inspection and condition evaluation
Design/built services
Value engineering
Highway and roadway design

BRIDGE PHOTOS

WHITESTONE BRIDGE

Tuned Mass Damper Removal, Miscellaneous Repairs and Opening of Selected Main Cable Panels for Inspection at the Bronx Whitestone Bridge,

Project No. BW14/84, MTA Bridges and Tunnels

The project involves monitoring and investigation of the conditions of the cable to assess the remaining cable strength. The main cables will be unwrapped in several locations and inspected. It will require removing existing cable rope suspenders and replacing with temporary ones.

LGM is involved in special inspection of the existing towers, design of miscellaneous structural steel repairs, and design of special jacking apparatus and temporary shoring system to remove and reinstall existing cable rope suspenders.

THROGS NECK BRIDGE

Roadway Deck Rehabilitation/Replacement for the Suspended Spans at the Throgs Neck Bridge.

Project TN-49, MTA Bridges and Tunnels.

LGM performed special bridge inspection, and develops and investigates various alternatives for new protective barrier.

Seismic and Wind Investigation at the Robert F. Kennedy Bridge,

Project RK-19, MTA Bridges and Tunnels

LGM is participating in Seismic Evaluation of the Ward and Randall’s Island Viaducts. The project scope involves development of complex multidegree-of-freedom 3D bridge models utilizing finite element analysis, evaluation of dynamic responses and fundamental modes of the structures, response spectrum analysis, bridge and individual bridge member vulnerability assessment and design of seismic retrofit measures.

RFK BRIDGE

George Washington Bridge, Replacement of the Palisades Interstate Parkway Helix Ramp, Fort Lee, New Jersey. Contract No. GWB 244.150, The PA of NY and NJ

LGM is participating in Design and Construction Support Services for replacement of the ramp from the Palisades Interstate Parkway to the George Washington Bridge. The existing helix ramp comprised of three bridges and two intermediate sections of roadway will be demolished and replaced with a new structure. The firm’s scope of services includes a load rating analysis of the existing structures, and development of conceptual demolition and erection procedures.

HELIX RAMP BRIDGES

Interim Repairs of Orthotropic Deck Structures at the

Throgs Neck Bridge for Project TN-82B, MTA Bridges and Tunnels

LGM provides Construction Support Services interim superstructure repairs, including reviews of steel shop drawings, various Contractor’s submittals, field changes and etc.

THROGS NECK BRIDGE

George Washington Bridge, Rehabilitation of 178th Street Ramp,

Bus Ramp and Bus Turnaround; Rehabilitation of Upper Level Sidewalk

The scope of services performed by LGM included special bridge inspection of the GWB Upper Level Sidewalk, structural analysis and design of the various existing superstructure elements required to be replaced and/or repaired, preparation of contract plans and specifications

GEORGE WASHINGTON BRIDGE

Design and Construction Support Services

Lower Level Deck Replacement at the Henry Hudson Bridge,

Project HH-80, MTA Bridges and Tunnels

The project involved a replacement of the existing bridge deck with a new concrete filled steel grid deck, steel structural repairs to existing roadway stringers, floorbeams, columns, installation of underdeck inspection platforms and rigging points, installation of new seismic isolation bearings at towers and abutments, and seismic retrofit and bearing replacement at the approach viaducts. LGM provided Construction Support Services including review and approval of shop drawings, load rating analysis of the existing structure and existing structure components for construction loads, analysis and design of various temporary structures, jacking and structural lifting operations, field changes and modifications.

HENRY HUDSON BRIDGE LOWER LEVEL

Design and Construction Support Services for Replacement of the Upper Level Deck and Toll Plaza and the Upper Level Curb Stringer and Safety Barrier at Henry Hudson Bridge,

Project HH-85 and HH10, MTA Bridges and Tunnels

These projects involve the replacement of a significant portion of the upper level deck, including the toll facility, and of the entire sidewalk and safety barriers. LGM was involved in structural analysis and design to retrofit

HENRY HUDSON BRIDGE UPPER LEVEL

existing floorbeans and columns supporting the upper Level Toll Plaza, sesimic analysis and seismic retrofit design of the existing retaining walls at the Manhattan Approach, and Construction Support Services including renew and approval of stell shop drawings, various Contractor's submittals and field changes and modifications during construction.

Investigation and Monitoring of Bridge Suspension System and Designs for Painting and Eye-bar Rehabilitation at the Bronx-Whitestone Bridge,

Project BW-84B, MTA Bridges and Tunnels

LGM was responsible for special inspection and investigation of Main Anchorages, and Anchorage Chambers of the main cables, conducting the infrared thermal image inspections to determine areas of water infiltration into the chambers, developing various retrofit measures to prevent water infiltration and eliminate corrosion of the main cables and eyebars and preparation of the inspection report.

BRONX WHITESTONE BRIDGE

Feasibility Study and Preliminary Design of Rivercrest Bridge over the Metro-North Railroad in the City of Fishkill.

LGM performed a feasibility study, preliminary analysis and design of a 300 ft long 3-span continuous bridge over the Metro-North Railroad in the City of Fishkill. The project scope included feasibility studies, preliminary analysis and design of the steel continuous superstructure with a composite concrete deck slab, design of 60 ft deep reinforced concrete drilled shafts, load rating analysis of the existing abandoned bridge to be utilized for erection of the new bridge, and development of a preliminary construction phasing.