competitive edge

  • ConSensor’s measurements sent by FTP connection in real time to the Office of Engineers of the city of Rotterdam, an extra service provided for this project
  • Know-how for detecting an increase in electrical conductivity at an early stage so that the necessary measures can be taken and the cause of moisture and/or (chloride) ion penetration can be found and addressed

ConSensor advantages

Project data

  • Project: Maas tunnel
  • Client: Ingenieursbureau gemeente Rotterdam
  • Architect: J.P. van Bruggen and Ad van der Steur
  • Renovation period: 2017 – 2019
  • Notable: The Maas river tunnel (1942) is the oldest underwater tunnel in the Netherlands

Long-term monitoring of concrete quality
The City of Rotterdam discovered that de-icing salt water had collected under the driving deck of the Maastunnel, corroding steel reinforcement in the bottom of the 1942 tunnel structure and threatening its integrity. To preserve and renovate it, its driving deck was removed, followed by the rotten concrete underneath. When they reached undamaged concrete, they laid down new reinforcing and poured a new layer of concrete, inserting sensors that allow Rotterdam to keep monitoring the concrete’s integrity into the future.

ConSensor measures the conductivity of the new concrete several times a day. When ConSensor gauges that conductivity is increasing—that is, that moisture and possibly (chloride) ions have penetrated into the concrete— the web platform shows the information, and the city can take measures to minimize damage. The earlier the cause is detected, the less the damage.