OPAC Consulting Engineers

Design Services


OPAC's creative approach to engineering design and problem solving has provided the background for design of numerous unique or unusual structural systems for bridges, transit stations, industrial structures, and buildings.

OPAC's designs are based on a commitment to rational forms, sound engineering judgements, quality aesthetic treatments, practical construction methods and the adoption of performance-based design principles from conception through construction.

Our arch bridges reflect this design philosophy applied to small and large structures in both steel and concrete. The use of classic forms with modern detailing provides an aesthetic design that is both timeless and appealing, as well as a structural design that is economical, durable, and maintainable.

Our cable-supported bridges bring creative thinking to another classic form. A balance of constructibility, aesthetics, and performance issues helps to provide an optimized solution.


OPAC offers the following design services:

Facilities/Struc­tures Design:                   Bridge Design:
River & strait crossing Pre- and post-tensioned concrete
Highway interchange Segmental concrete box girders
Pedestrian / bicycle overcrossing    Multi-cell concrete box girders
Elevated viaduct Cable stayed
High speed rail Suspension
Rapid transit Steel box girders
Thin shell concrete dome Steel plate girders
Long-span structure Steel arch
Special / unusual structure Concrete arch

Selected OPAC Design Projects: (31 Total, 5 on this page)


BART Warm Springs Extension - Design

BART Warm Springs Extension

Design of a 5.4 mile BART extension

Fremont, California. Construction completion 2011

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Nanning Bridge - Design

Nanning Bridge

A 300 m span steel arch bridge across the Yong River. The arch ribs are steel box sections and the deck consists of a steel box girder with an orthotropic deck.

Nanning City, China. Construction completed 2009

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BART Earthquake Safety Program - Seismic Retrofit Design

BART Earthquake Safety Program

Performed seismic vulnerability studies on multiple BART viaducts

San Francisco Bay Area, California. Design completed 2009

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Shenzhen Western Corridor Bridge - Design Supervision

Shenzhen Western Corridor Bridge

Design supervision and review for a 3.8 km long bridge between Shenzhen and the Hong Kong SAR, with separate 210 m span asymmetrical single-tower cable-stayed units across two navigation channels, and 75 m span concrete box girder viaducts.

Shenzhen, China. Construction completed 2005

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Third Carquinez Strait Bridge - Design

Third Carquinez Strait Bridge

A 728 m span suspension bridge with a steel orthotropic deck. The new suspension bridge replaced a 75 year old truss bridge across the Carquinez Strait.

Sacramento River, Crockett - Vallejo, California. Construction completed 2004

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