Seismic Design in Geotechnical Engineering

Seismic design is a critical component of geotechnical engineering, particularly in seismically active regions such as British Columbia (BC). It focuses on how soil and rock respond to earthquake-induced ground motion and how these responses influence the stability and performance of foundations, slopes, and retaining structures.

Key aspects of seismic geotechnical design include:

• Site-Specific Ground Motion Analysis
  Evaluation of expected seismic shaking based on regional seismic hazard maps, local geology, and soil amplification effects.

• Soil–Structure Interaction
  Assessment of how dynamic earthquake loads transfer between the ground and structures, especially for deep foundations and buried infrastructure.

• Liquefaction Assessment
  Identification of loose, saturated soils that may lose strength during seismic shaking, potentially causing settlement, lateral spreading, or bearing capacity failure.

• Seismic Slope Stability
  Analysis of the potential for earthquake-triggered landslides or slope failures, particularly in steep terrain or engineered fill embankments.

• Earthquake-Induced Earth Pressures
  Design of retaining walls and buried structures to safely resist transient lateral loads generated during seismic events.

• Performance Objectives
  Structures are designed to meet defined performance goals, such as remaining operational after minor earthquakes and preventing collapse during major seismic events.

Seismic design practices follow recognized national and international standards, including ASCE/SEI 7 and AASHTO LRFD, and may involve both prescriptive methods and advanced numerical modeling. In British Columbia, designs also account for local fault systems, historical seismicity, and site-specific response spectra.

Ultimately, seismic design goes beyond structural survival—it ensures that infrastructure remains safe, functional, and reliable, even under extreme earthquake conditions.