Design and retrofit of buildings in the urban cores of seismically vulnerable regions present several unique seismic, geotechnical, geologic, and constructability challenges. In close collaboration with leaders in academia, the engineers at ENGEO developed precise methodologies for performing seismic-hazard and site-response analyses for new structures and existing buildings. These approaches allow us to provide optimized earthquake engineering, typically resulting in much more efficient superstructure designs in seismically active urban environments. ​

Understanding PLAXIS GRA with PM4Sand: A Geotechnical Insight

As shown in this video, ENGEO uses advanced modeling techniques to improve earthquake resilience at a waterfront site in San Francisco. The first part shows the impact of ground shaking on the existing conditions, while the second part demonstrates how a soil-cement-mixed buttress can stabilize the site and reduce deformations.

ASCE 7-22 Critical Geotechnical Updates: What You Need to Know

The ASCE 7-22 standard will be implemented in the next California Building Code that will take effect on January 1, 2026. The seismic design provisions of ASCE 7-22 include significant advancements relative to its predecessor, ASCE 7-16, leading to enhanced structural resilience against earthquakes. A notable change is the introduction of more refined site classes, which are based primarily on the average shear-wave velocity in the upper 100 feet or 30 meters (VS30), providing a standardized and precise basis for site classification. Additionally, ASCE 7-22 includes more robust guidelines for calculating vertical response spectra and requirements for estimating downdrag on deep foundations in liquefiable soils. These changes generally improve the accuracy of seismic design parameters; however, they may also have project impacts including certain insurance requirements. For example, changes in site class designation can influence risk assessments and premiums. This is particularly true for softer site classes (Site Classes D, DE, and E). Although the general seismic criteria in ASCE 7-22 are greatly improved relative to ASCE 7-16, there are still many sites where a site-specific analysis will produce significant refinement relative to the general parameters. ENGEO would be happy to work with you to determine how these changes may affect your future projects and how our advanced seismic hazard and numerical modeling analyses can help optimize designs to benefit your project goals.

ENGEO's Contributions to Chapter 21

David Teague, PhD, GE, serves as a corresponding member of the 2026 National Earthquake Hazards Reduction Program (NEHRP) Provisions Update Committee (PUC). The NEHRP provisions document is a technical resource for updates to U.S. building codes and standards (e.g., ASCE 7). David serves on a team that focuses on ground-motion and geotechnical issues. Specifically, David is involved in a re-write of Section 21.1, which pertains to site-response analysis procedures. Additionally, David is also involved in efforts to identify when site-response analysis should be required at sites with a liquefaction hazard.

ENGEO Marks Third Year with EERI, Advancing Earthquake Resilience

For the third consecutive year, ENGEO is proud to be a subscribing member of the Earthquake Engineering Research Institute (EERI), an organization dedicated to reducing earthquake risk and promoting resilient communities. EERI's mission to advance earthquake engineering aligns with ENGEO’s role as a leader in the industry, where we provide innovative solutions to complex geotechnical and seismic challenges. Through this partnership, ENGEO continues to contribute to cutting-edge research and promote seismic safety, helping build safer, more resilient structures and communities worldwide. 

Recent News: California Hospitals Work to Meet Earthquake Retrofit Deadline

California hospitals are striving to meet the 2030 earthquake retrofit deadline, yet many face intensified challenges, especially after the government’s rejection of a request to extend the compliance timeline. Securing adequate funding is a significant hurdle, with more than half of the state’s 420 hospitals operating at least one building that may not be functional following a major earthquake. ENGEO, leveraging its expertise in seismic engineering, offers innovative, data-driven solutions that optimize seismic demands, leading to substantial cost savings and making many retrofit schemes financially feasible and achievable for healthcare facilities. 

"Lucas Museum of Narrative Art is a geometrically complex, base isolated structure, located in Los Angeles. Achieving an enhanced set of design criteria for displacements and accelerations, while not exceeding pre-established moat dimensions, required more sophisticated thinking. This thinking came from the engineers at ENGEO who developed the design ground motions at the site using non-ergodic methods, which prior to our project had only been used in academic settings. Our project was the first commercial application of non-ergodic site response. Not only did ENGEO’s work result in a better understanding of ground motions that helped us to achieve the project’s structural design criteria, but they also seamlessly helped ferry this new thinking through Los Angeles Department of Building and Safety." - Dan Sesil/ LERA