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TUNA plus is the NATM (New Austrian Tunneling Method) tunnel analysis program which is specially designed to be used for practicing engineers in the fields of tunnel design, construction, or supervising.   TUNA plus has fully automated built-in pre, main, and post processors so that users having no numerical analysis background can analyze NATM tunnels.

Software Requirements

  • Windows 64 Bit Operating System

  • Intel Pentinum 4 or AMD Processor

  • 4 GB Ram with 30 GB Free Space in Drive C

  • SVGA Monitor


  • Nonlinear Liner-Medium Interaction

  • English and Metric Units

  • Multi-Staged Excavations

  • Multi-Layered Geological Medium

  • Plain or Reinforced Concrete Liners

  • Shotcrete and Rock Bolt Installation

  • Tunnel Geometries
    Single Tunnel (Half Section)
    Single Tunnel (Full Section)
    Symmetric Two Tunnels
    Unsymmetric Two Tunnels

  • Liner Loads - Weight, Water Pressure, Loosening Load
    Support Degradation

  • Tunnel Shapes- Circular, Horseshoe, User Defined


  • Ground Surface Settlement

  • Tunnel Deformed Shape

  • Contours of Safety Factor

  • Axial Stresses of Rock Bolt

  • Deformed Shape of Liner

  • Stresses in the Reinforcing Bars

  • Stresses in the Extreme Fiber of the Liner

  • Bending Moment, Thrust, and Shear in the Liner

  • Principal Stress in the Surrounding Medium and Shotcrete

  • Displacement History at Ground Surface, Tunnel Crown, Spring Line,
    and Invert.

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