OPAC Consulting Engineers

Evaluation Services


Evaluation of structures using advanced analytical capabilities has been a core part of OPAC's engineering services since the inception of the firm. Our expertise centers in two areas: Dynamic Analysis and Time-dependent Analysis.

OPAC's dynamic analysis experience includes studies of seismic vulnerability, fatigue effects, aerodynamic performance, and dynamic impact response to high-speed rail loads. Our dynamic analysis capabilities can incorporate nonlinear inelastic characterizations of soil, foundations, cables, concrete, and steel components.

OPAC can provide time-dependent analysis for complete stage-by-stage evaluations of stresses, strains, and deflections for structures.

OPAC has successfully provided evaluation services to our clients on some of the largest and most important transportation structures in North America, Asia, and South America:


OPAC offers the following evaluation services:

Advanced Structural Analysis:              Evaluation of Structures/Brid­ges:
Time-history analysis Precast segmental bridge
Soil-structure interaction analysis Cast-in-place segmental bridge
Nonlinear dynamic analysis Concrete girder bridge
Inelastic analysis Cable-stayed bridge
Seismic evaluation Suspension bridge
Wind engineering Steel box girder bridge
Rolling stock analysis Arch
Time-dependent analysis Concrete dome
Collapse analysis Pedestrian bridge


Selected OPAC Evaluation Projects: (30 Total, 5 on this page)


Memorial Causeway Bridge - Engineering Investigation

Memorial Causeway Bridge

Engineering investigation of a segmental bridge that consists of a nine-span 2,340 ft long concrete girder.

Clearwater, Florida. Investigation completed 2009

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Ringling Causeway Bridge - Engineering Investigation

Ringling Causeway Bridge

Engineering investigation of a segmental bridge having structural issues during construction.

Sarasota, Florida. Investigation completed 2009

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Tappan Zee Bridge - Peer Review

Tappan Zee Bridge

Performed peer review of a cantilever truss bridge with a main span of 1,212 feet which was constructed across the Hudson River in New York.

Tarrytown - Nyack, New York. Peer review completed 2008

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Manhattan Bridge - Value Analysis

Manhattan Bridge

Value analysis for seismic assessment and retrofit of a historic suspension bridge.

Brooklyn-Manhattan, New York. Value analysis completed 2007

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Bay Division Pipelines 1 & 2, Dumbarton Crossing - Seismic Vulnerability Study

Bay Division Pipelines 1 & 2, Dumbarton Crossing

Seismic vulnerability study of the San Francisco Public Utilities Commission's major water pipelines.

Palo Alto-Newark, California. Study completed 2006

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