Tunnel Engineering

Planning, designing and constructing tunnels presents some of the most formidable challenges in the field of geoengineering. Our engineers and geologists are experienced designers of tunnels for transportation, water and wastewater, and hydroelectric use. Providing practical tunnel designs that minimize owner risk and reduce construction cost is our goal, and a collaborative, multidisciplinary approach is how we attain it.

Constructability and function are key aspects of our design process, and we are flexible when it comes to meeting the increasing demands of different project delivery methods. We are not only tunnel design and construction specialists; we are also skilled project managers and valuable contributors to project teams.

We tailor our services on tunnel and underground projects to address the unique and specific needs of our project partners, whether they are owners, engineering teams, or contractors.

Our tunneling solutions include:

For Owners and Engineering Teams

  • Geotechnical evaluations for underground projects
  • Feasibility studies, evaluation of alternatives
  • Coordinated detailed design calculations, drawings, specifications, and geotechnical contract documents for tunnels, shafts, and geotechnical instrumentation
  • Cost estimates based on experience as contractors
  • Management of risk factors in design and construction
  • Construction management
  • Inspection and rehabilitation designs for existing tunnels
  • Emergency response problem analysis and remedial action plan/design
  • Claims review and cost analysis, expert witness work

For Contractors

  • Pre-bid evaluation of geotechnical bid documents and contract specifications
  • Tunnel support design and submittals
  • Excavation support design and submittals
  • Geotechnical instrumentation design and submittals
  • Value engineering change proposals
  • Claims support

Tunnel Engineering

  • Siting and feasibility studies, including geotechnical exploration and lab testing programs
  • Preliminary and final design
  • Initial ground support for tunnels and shafts
  • SEM/NATM design
  • Precast concrete segmental lining
  • Grouting and ground improvement design
  • Numerical modeling
  • Preparation of contract documents (plans, specs, GDMs and GBRs)

Constructability & Cost Estimating

  • Evaluation of designs for constructability
  • Estimates at all project development stages based on contractor experience
  • Bid or bid-check estimates for contractors using HCSS HeavyBid software

Risk Management

  • Risk register development
  • Qualitative risk analysis
  • Mitigation measure tracking and verification
  • Probabilistic quantitative analyses of cost and schedule impacts
  • Budget and schedule contingency analysis

Construction Engineering

  • Pre-bid geotechnical and contract document evaluations
  • Cost estimating
  • Excavation staging and support design
  • Tunnel and shaft design
  • Ground modification design
  • Value engineering
  • Geotechnical instrumentation and monitoring
  • Structural geologic mapping/evaluation
  • Claims analysis and support

Construction Management

  • Contract management
  • Construction inspection
  • Resident engineer services
  • Submittal review
  • Construction claims analysis

Trenchless Technology

  • Selection of trenchless methods and equipment
  • Assessment/characterization of geotechnical conditions
  • Jacking/receiving pit design
  • Geotechnical contract documentation preparation

Inspection and Rehabilitation

  • Facility inspection
  • Evaluation of existing ground support and structure
  • Evaluation of existing geotechnical and groundwater conditions
  • Preparation of rehabilitation design alternatives
  • Development of re-entry safety and ventilation procedures