Caltrans Regional Transportation Management Center, Irvine, CA
Caltrans Regional Transportation Management Center, Irvine, CA



Completion Date

(Geotechnical Report)

DYA Client

DMJM Harris

Project Cost

$3 Million

Project Description

Diaz•Yourman & Associates (DYA) provided geotechnical services for a Caltrans essential services facility to manage automobile traffic in Orange County. The facility was designed to be operational after a major earthquake (10 percent probability of exceedance in 50 years) and to help direct emergency operations. The two-story building was supported on shallow foundations using a base isolation system. The foundations system was excavated into the ground to produce a first-floor level with surrounding ground surface. Preliminary recommendations were provided two weeks after the field investigation to expedite the design. Geotechnical services included performing a complete geological/seismic review in accordance with California Geological Survey (formerly California Division of Mines and Geology) CDMG Note 48 and developing earthquake ground motions, response spectra, and time history records. Division of State Architect and California Geological Survey reviewed and approved the geotechnical engineering report. Geotechnical recommendations were also provided for cast-in-drilled-hole foundations for a Communications Tower.

Allen M. Yourman, Jr., PE, GE – Geotechnical Manager

V.R. (Nadesh) Nadeswaran, PE, GE – Project Engineer

Gerald M. Diaz, PE, GE – Geotechnical Principal

Our Services


  • Site and route evaluations
  • Geologic hazards
  • Seismic design
  • Site characterization
  • Subsurface drainage
  • Grading
  • Ground improvement
  • Slope stability
  • Foundations
  • Dynamic analyses
  • Pavements
  • Instrumentation


  • Material sources
  • Construction observation and testing
  • Verification of anticipated conditions
  • Evaluation of changed conditions
  • Foundation installation
  • Instrumentation
  • Claims evaluation


  • Site characterization
  • Remediation
  • Solid and liquid waste disposal
  • Landfill
  • Aerially Deposited Lead (ADL) Studies
  • Phase I Initial Site Assessments (ISA)
  • Phase II Hazardous Waste Studies
  • Sustainability


  • Forensic investigation
  • Litigation support

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