Seismic Evaluations

Southern California is located within a seismically active environment containing numerous faults located below and adjacent to high population centers. The potential for strong ground motion generated from active faults requires special consideration when designing residential, commercial, public school, hospital, and essential services buildings and associated infrastructure. Through detailed geological and seismological site characterization, LGC provides critical information for use by structural engineers and governmental agencies in land planning, structural design, and emergency preparedness.

We take a conservative approach in our evaluation and implement established guidelines and the latest seismic catalog databases from sources including the California Geological Survey, the United States Geological Survey, the Uniform Building Code (UBC), California Building Code (CBC), International Building Code (IBC), and published scientific research. We work closely with the structural engineer to determine the appropriate methodology for evaluation, based upon the scope of the project and its intended use. From the results of our tailor-made analyses, we can provide a wide range of seismic design parameters including estimated peak ground acceleration with return periods and probability of exceedance, dynamic response spectra, and active fault near-source seismic factors, among others.

Another aspect of our seismic evaluation capabilities includes active fault investigations. Our Certified Engineering Geologists have an extensive background in formulating and implementing field investigations, and evaluating recent fault movement through detailed aerial photograph review, field geologic mapping, and fault trench logging.