Geo-Advantec, Inc. offers comprehensive services in various areas from site feasibility evaluation through project completion for a wide range of projects. Our highly qualified team of professionals has extensive experience in performing a variety of complex geotechnical engineering projects and providing innovative solutions for complex projects.

In addition, our diverse team of field technicians and inspectors with related technical backgrounds, education, and accreditations are well experienced to support the construction course of projects. Geo-Advantec, Inc. is vastly specialized to provide the following services:

Geotechnical engineering is a branch of civil engineering dealing with the analysis, design, and construction of foundations, slopes, retaining structures, and other systems that are made of or supported by soil or rock. Geotechnical engineering is essential to the foundation design for every existing or new structure, highway, bridge, tunnel, harbor, airport, water line, reservoir, etc. Commonly, the geotechnical engineering service comprises a study of subsurface conditions using various sampling, in-situ testing, and/or other site-characterization techniques, performing engineering analyses, and providing geotechnical solutions and recommendations to build improvements.

Geo-Advantec team has performed numerous geotechnical engineering evaluations and investigations for different types of projects worldwide and in Southern California. Our projects include developments of schools and colleges, seismic retrofit of structures, solar energy, cell towers, roads and bridges, tunnels, cooling towers and stacks for power plants, parking structures, main water and sewer lines, recycled water and utility lines, sports facilities, parks, and recreational facilities. We provide comprehensive soils/underground studies based on the project-specific requirements. The following is a list of services under this category:

  • Geotechnical Field Explorations/Investigations
  • Ground Water Evaluation
  • Foundation Design/Recommendations
  • Shallow Foundation System Analysis
  • Deep Foundation System Analysis
  • CAPWAP, PDA Testing and Analysis
  • Pile Integrity Testing
  • Vibration Monitoring
  • Settlement Analysis
  • Ground Motion Response Spectra
  • Liquefaction and Seismic Settlement Analysis
  • Slope Stability Investigation, Analysis, and Design
  • Lateral Earth Pressure Analysis
  • Tie-Back/Soils Nailing Analysis
  • Instrumentation and Monitoring
  • Stability Evaluation of Excavations

Engineering geology is the application of geologic sciences to the engineering aspects of a project to assure that the geologic factors and hazards in regarding the location, design, construction, operation, and maintenance of engineering works are recognized and incorporated into the design of a project. Engineering geologists investigate and provide geologic recommendations, analysis, and design associated with site development. The expertise of the engineering geologist is essentially in earth-structure interactions and investigation of how the earth or earth processes impact human-made structures and human activities.

In geographic zones such as Southern California, where seismic hazard plays a significant role in the design of safe structures, no comprehensive geotechnical evaluation can be done without having an engineering geology insight about the project. GAI’s geologists/engineering geologists are highly competent and experienced in providing several related services such as:

  • Fault Trenching and Evaluation
  • Seismic Hazard Evaluation
  • Geologic Mapping
  • Landslide Evaluation
  • Slope Stability Evaluation
  • Subsurface Exploration and Downhole Logging
  • Aerial Photography Review
  • Review of Geologic Literature

Geotechnical earthquake engineering can be defined as that subspecialty within the field of geotechnical engineering that deals with the design and construction of projects to resist the effects of earthquakes. Geotechnical earthquake engineering requires knowledge of basic geotechnical principles as well as an understanding of geology, seismology, and earthquake engineering.

Geo-Advantec professionals have performed comprehensive geotechnical, geological, and geohazard investigations for seismic rehabilitation of several projects in southern California. The scope of our work included conducting field borings, field geophysics study, performing site-specific seismic hazard analysis per USGS, CGS, CBC, and ASCE-41 guidelines, providing different site response spectra, liquefaction study, and stability evaluation during earthquakes. In the field of geotechnical earthquake engineering, our services include:

  • Seismic Hazard Evaluation
  • Ground Motion Studies
  • Seismic Lateral Displacement of Slopes and Settlement
  • DSHA, PSHA, and Site-Specific Studies
  • Liquefaction and Seismic Settlement Analysis
  • Ground Motion Response Spectra
  • SSI Modeling/Response Spectra

In general, the combined effect of elastic, plastic, and viscosity parameters creates soils deformation. Thus, soils behavior becomes complex and hard to predict. Geotechnical engineers predict ground behavior using finite difference or finite element computer modeling. However, the complexity of the soil profile and loading conditions in some cases makes the performance of the soils far from the predictions. Geotechnical instrumentation fills the gap between prediction and performance. It helps prevent soil mass failure as well as damage to structures on the ground. Geotechnical Instrumentation, on the one hand, monitors structural and soils deformation, stresses on structural elements, and groundwater pressure and inflows. On the other hand, it provides construction control and performance monitoring for safe construction.

Where limited geotechnical instrumentation may be used for simple projects, it is crucial for the successful completion of critical and complex projects such as tunnels, slopes, deep excavations near sensitive structures, etc. In general, the process of applying geotechnical instrumentation to a project includes the following steps:

  • Monitoring System Design
  • Procurement and Supply
  • Installation, Commissioning, and Testing
  • Baseline Readings
  • Monitoring and Data Presentation
  • Decommissioning

Geo-Advantec team has completed several unique instrumentation projects, some in Southern California. We specialize in the design, installation, monitoring, and data analysis of instrumentation projects.

Pavement Engineering is a branch of civil engineering that uses engineering techniques to design flexible (asphalt), rigid (concrete), or composite pavements. This includes streets and highways and involves knowledge of soils, traffic engineering, and material properties. Pavement engineering involves the design and construction of new pavements, as well as rehabilitation and maintenance of existing pavements.

Geo-Advantec team has completed numerous pavement study and design projects for public agencies in Southern California, including the Cities of Commerce, Compton, Covina, Downey, Industry, La Mirada, Pomona, San Dimas, and several Caltrans/Metro highway projects.  We have also designed runway and taxiway pavement sections for Palmdale Air Force Base.

Our services in this category include the following items:

  • Pavement Management Program/Survey
  • New Pavement Design
  • Life-Cycle Cost Analysis (LCCA)
  • Pavement Rehabilitation Study and Design
  • Value Engineering of Pavement Projects
  • Distress and Failure Cause Study of Pavements
  • Asphalt Laboratory Testing
  • Pavement Field/Batch Plant Inspection and Testing

A forensic engineer investigates the damage or the reasons for a failing structure and/or its components and determines the cause of the problem. The forensic engineer may also have to determine the responsible party for the damage/failure and provide expert witness services. They may also need to have under oath testimonial appearance in a court of law.

Forensic geotechnical evaluation applies science and engineering within the rules and practices of the legal system to represent reality and resolve conflicts. To provide the required assistance in the settlement of disputes, extremely qualified geotechnical professionals need to combine high-quality forensic investigations with engineering science to clearly present the matters being disputed.

The foremost quality of a forensic engineer is to be an expert in the field of the matter. The expert knowledge is acquired by the combination of advanced education and substantial experience in the field of expertise.

The long-term performance of all engineering structures such as buildings, bridges and roadways, highly depends on the soundness of the supporting soils and foundation system. Continuous observation and testing of grading operations and foundation construction are required to assure the long-term performance of the project and to ascertain that the end product complies with the specification and fulfills the lifetime service needs of the project. The GAI team of experienced field engineers and technicians provides the following “during construction” services:

  • Mass Grading Monitoring
  • Shoring System Installation monitoring and Tie-Back Testing
  • Soils Nailing and Anchoring Observation and Performance Testing
  • Caissons and Drilled Piles Construction Observation
  • Driven Pile Observation Pile Dynamic Testing/Analysis and Integrity Evaluations
  • Pavement Sub-grade, Aggregate Base, and Asphalt/Concrete Field Testing
  • Foundation Excavation Observations
  • Field Density Testing
  • Observation and Testing of Soils Stabilization Projects

Material testing services include the process of testing, analyzing, and certifying various types of field and construction materials to ensure that the specifications comply with project requirements and pertaining codes. The following is a summary list of some of the laboratory testing services we provide:


  • Atterberg Limits
  • Consolidation
  • Density
  • Direct Shear
  • Durability Index
  • Expansion Index
  • Hydrometer Analysis
  • Maximum Density
  • Moisture Content
  • R- Value
  • Specific Gravity
  • Soundness
  • Swell
  • Sieve Analysis
  • #200 Wash
  • Sand Equivalent
  • Unit Weight
  • Asphalt Extraction
  • Marshall, Hveem
  • Resistivity
  • pH
  • Sulphate
  • Chloride
  • Corrosion Series
  • Unconfined Compression


  • Concrete Compression Strength
  • Concrete Flexural Strength
  • Aggregate Gradation
  • Concrete Air%, Slump, Unit Weight
  • Rebar Tensile/Bend Test
  • Masonry Units and Masonry Prism

To assure compliance of any project with approved plans, specifications, and contract documents, as well as compliance of the performed tasks with the applicable codes and regulations, inspection of materials and construction activities becomes an important part of the Quality Control/Quality Assurance program.

Geo-Advantec provides qualified and experienced special inspectors certified in multiple disciplines to observe construction activities and perform quality control tests. We provide special inspection services for different work categories, including, but not limited to the following:

  • Soil
  • Concrete
  • Reinforcing Steel (Rebar)
  • Masonry
  • Structural Steel and Welding (Shop and Field)
  • Prestress Concrete
  • Fireproofing
  • Source Inspection