Skip to main content


Consultation, service life management, condition assessment, restoration

The inner and outer surfaces of the supporting constructions of tunnels are often exposed to an aggressive environment, e.g. ground water containing chloride and sulphate or deicing salt brought in from outside. Insufficient consideration in the design phase can lead to extensive damage of severely exposed components after a relatively short service period. If the exposure effects are taken into account during the design process, the service life of tunnels can be extended considerably. Damage occurring during the use of tunnels must be found easily, quickly and reliably. If repair is necessary, customized, economical and time-optimized concepts must be often be developed. We offer the following services:

  • Expert advice for structural planners and clients during the design phase, tendering and execution of new as well as the restoration of existing tunnels
    • Recommendations for optimizing concrete composition with respect to the expected exposure conditions (e.g. chloride, freeze-thaw deicing salt)
    • Conceptual design, coordination and evaluation of preliminary laboratory and in situ tests (sample surfaces)
    • Technical support during the drafting of the contract documents
    • Surveillance of certain measures (e.g. cathodic corrosion protection, special surface protection systems)
    • Expert assistance during construction
  • Development of customized service life management systems (design, execution, monitoring, maintenance)
  • Assessment of state of existing tunnels using non-destructive testing (e.g. tunnel lining inspection, concrete cover measurements, GPR, ultrasonic echo measurements)
  • Advice on concrete technology for clients and contractors before and during the construction of a new tunnel or restoration work
  • Expert assessment of construction quality taking into account the contractual agreement
  • Development of restoration concepts and planning of repair measures (conventional restoration, CCP) for all service phases defined by HOAI