Geotechnical Services

The Problem

Even a strongly-built structure with an excellent design will not stand on a bad foundation. Although the structure will carry its loads, the earth beneath it may not. The displacements due to inadequate foundations may alter the stress distribution significantly within a structure, leading to cracks and, eventually, failure. The Leaning Tower of Pisa is a famous example of a bad foundation but there are many others. The old armory in St. Paul, Minnesota, another strong building erected on a poor foundation, sank 20 feet or more into soft clay.

Since the eighteenth century, the need for better design of structural foundations has led scientists and engineers to analyze soil characteristics and to study soil problems in the same manner like other problems in structural design. Investigators turned their attention to the mechanics of soil masses, and developed expressions for earth pressure on walls and the bearing capacity of foundations.

Following in the footsteps of those early geotechnical pioneers, SAI has its own geotechnical/geological staff prepared to address issues related to geotechnical engineering.

The Solution

SAI offers Geotechnical Services for a wide variety of projects including: multi-story residential and commercial buildings; schools; garages; earth retaining structures; bridges; highway embankments; earth dams; transmission towers; rigid and flexible pavement; and ground improvement.

    SAI has successfully met the following geotechnical challenges:

  • Designing deep foundation systems for different commercial and residential structures in various soil types
  • Performing ground improvements to reduce settlement in paved parking areas and roadways
  • Designing earthen dams to retain water in manmade ponds
  • Designing earth supporting systems, such as sheet pile walls and mechanically-stabilized earth walls
  • Analyzing in-situ instrumentation data (e.g., settlement platforms and inclinometers) and providing recommendations to ensure stability and safety of structures based on the instrumentation readings

Services

Our Range Of Sevices

  1. Design Work

    • Preparation of subsurface investigation programs
    • Evaluation of design soil parameters utilizing field data and laboratory test results
    • Analysis of shallow and deep foundations
    • Analysis and recommendations for construction on problematic soils/rocks
    • Settlement analysis and measures for reducing post-construction settlement including preloading, wick drains and use of lightweight fill
    • Slope stability analysis
    • Seepage analysis
    • Design of earth retaining structures including sheet pile walls, soldier piles and lagging, braced excavation, and mechanically-stabilized earth walls
    • Design of pond/reservoir liners over side slopes involving geosynthetic clay liners and geocell systems
    • Pavement design
    • Analysis of in-situ instrumentation data
  2. Preparation of Contract Documents

    • Geotechnical Reports
    • Technical Specifications and Bidding Documents
    • Quality Control/Quality Assurance Programs
    • Construction Drawings
  3. Supervision of Field Inspection and Construction Oversight

    • Inspection of test borings, test pits, groundwater monitoring wells, and piezometers
    • Inspection/oversight of pile driving and pile load tests
    • Inspection/oversight of placement and compaction of landfill caps constructed using natural soils and geosynthetics
    • Inspection of the installation of instrumentation equipment, including inclinometers, extensometers, settlement plates, and piezometers
  4. Geotechnical Testing

    • SAI is home to a soil mechanics laboratory for testing the physical and mechanical properties of soils. A partial list of the laboratory’s testing capabilities can be found on this website under the Geo-Environmental Services page.
    • In-situ testing:
      • Measurements of Soil Density and Moisture Content using the Nuclear Method
      • Evaluation of soil infiltration rates using the Double Ring Infiltrometer Test and Percolation Test as per NJDEP requirements