Geotechnical Design

From the simplest to the most highly complicated geotechnical solution, EEI’s Geotechnical Design Division provides our clients with the most appropriate and cost-effective solution for a project's requirements.  EEI’s geotechnical design engineers have a wide range of expertise of all facets of geotechnical engineering.  The Geotechnical Design Division staff of EEI has comprehensive experience in:

• Shallow and deep foundation design
• Soil deformation and hydraulic analyses and instrumentation design
• Geosynthetic engineering and design
• Retaining wall design
• Temporary shoring design
• Forensic analyses and expert witness services. 

Shallow and Deep Foundation Design

In support of the numerous subsurface investigations performed by EEI, the Geotechnical Design Division routinely develops foundation recommendations for commercial, industrial, and residential buildings.  Shallow foundations recommendations for spread footings and mat foundations are developed whenever possible to provide cost-effective foundations.  Where bearing soils are either too weak or are susceptible to intolerable vertical deformations, deep foundation recommendations are developed.  EEI’s Geotechnical Design Division regularly determines axial resistance, lateral resistance, and uplift resistance of deep foundation systems including H-piles, timber piles, pipe piles, auger cast piles, mini piles, and caissons.  

In addition to providing geotechnical design support for building foundations, EEI’s Geotechnical Design Division has extensive experience in foundation design for transportation structures such as highway bridges and retaining walls, light standards, sign structures, dynamic message boards, and railroad bridges and retaining walls.

Soil Deformation and Hydraulic Analyses

By performing detailed deformation analyses of subsurface conditions, EEI’s Geotechnical Design Division is able to provide cost-effective alternatives to provide acceptable site improvements.  Unacceptable vertical deformations associated with elastic settlement, consolidation, and creep can be brought to within tolerable limits by partial soil exchanges, surcharging, lightweight fills, or by reducing applied loads through geosynthetic bridge lifts.  EEI’s Geotechnical Design Division has provided numerous recommendations for improving time periods for soil consolidation through surcharging with and without wick drains.

Overall stability of soil slopes is routinely evaluated by EEI’s Geotechnical Design Division.  When the shear strength of subsurface soils is inadequate to support proposed slopes, EEI’s Geotechnical Design Division can improve stability using staged construction, geosynthetic reinforcement, or soil nails and rock anchors.

EEI’s Geotechnical Design Division is frequently required to provide hydrogeology analyses for temporary and permanent dewatering for below grade structures, temporary dewatering for excavations, and dam remediation and permanent dam hydraulic performance.  Design of temporary and permanent dewatering systems including well point location and depths, pump sizing and volumetric requirements can be provided for small and large projects.

On projects where development overlies weak overburden soils, EEI can develop construction approaches supplemented with instrumentation design and monitoring to provide satisfactory stability and long-term performance.  Improvement of weak overburden can include staged construction, light weight fills, surcharging with and without wick drains, and other soil improvement techniques such as deep dynamic compaction and compaction grouting.  Instrumentation design and monitoring designed by EEI include settlement monitoring, excess pore pressure dissipation and inclinometers.

Geosynthetic Engineering and Design

EEI’s Geotechnical Design Division is recognized for its expertise in geosynthetic materials in civil engineering applications.  With extensive knowledge in geogrid, geotextiles, geomembranes, geonets and geocomposites, the application of these cost-effective materials are routinely featured in EEI’s designs.

Retaining Wall Design

As a regional leader in retaining wall design, EEI’s Geotechnical Design Division has extensive experience in design of nearly every type of retaining wall.  From residential, commercial, industrial, and transportation projects, EEI can develop the most appropriate, cost-effective retaining wall design for any project.  Retaining wall systems that can be provided by EEI include reinforced concrete cantilever, gravity segmental, mechanically stabilized earth, geosynthetic-reinforced segmental, stabilized aggregate backfilled segmental, soldier pile and tie-back walls.  Hybrids of various retaining wall systems are commonly provided where project constraints require maximum flexibility of the retaining wall system.

On many projects where limited geometry is available for site development, EEI’s Geotechnical Design Division has augmented retaining wall designs with required features to provide safe, durable structures.  Where retaining walls abut streams and rivers, EEI estimates the maximum stream velocity and scour anticipated and designs for appropriate scour protection for the retaining wall.  For applications where vehicular barriers are required at the top of the retaining wall, EEI evaluates the vehicular design criteria and develops design of vehicular barrier system necessary to provide adequate protection for vehicular traffic at the top of the retaining wall.

Temporary Shoring Design

EEI’s Geotechnical Design Division provides temporary shoring designs for construction projects where limited geometry is available to provide safe excavations.  From the most simplistic trench design to the most advanced pile and lagging design, EEI has provided shoring designs for many construction projects.  Shoring solutions include sheet pile, pile and lagging, and shotcrete fascia with tie-backs.  By employing tie-backs, deadmen or rakers, EEI is able to minimize section sizes to provide cost-effective solutions.

Forensic Analyses and Expert Witness Services

EEI’s geotechnical experts are frequently called upon to provide emergency recommendations, remedial designs and forensic analyses when geotechnical engineering systems become problematic.  EEI has extensive experience in providing technical contributions for litigation support and in providing expert testimony.