OPAC Consulting Engineers

Seismic Capabilities

OPAC maintains leading-edge technologies for seismic evaluation and design of structures. We have developed and refined these technologies for their use on some of the largest and most important transportation structures in western North America, Asia, and South America.

OPAC can apply a wide range of seismic engineering tools, appropriate to the type of structure including its seismic exposure and level of expected performance. This can be used for initial investigations, parameter studies, design development, and final design of a wide variety of structures.

OPAC principals directed the precedent-setting seismic evaluation and retrofit strategy studies of the Golden Gate Bridge in the late 1970's prior to the founding of OPAC. We have since advanced the state-of-the-art technology on many projects for which OPAC held seismic design or analysis responsibilities.

OPAC's technological analysis and design capabilities applied to those projects include:




Global and local dynamic modeling and analysis.

Time-history analysis including multi-support excitation.

Soil-structure interaction analysis, including discrete and continuum approaches.

Nonlinear dynamic analysis, including large displacement and inelastic effects.

Local inelastic analysis of concrete and steel components.

Evaluation of energy dissipation / isolation devices.

Design of seismic resistant components and systems.