Extended service life of concrete structures by the use of embedded sensors

Title: Extended service life of concrete structures by the use of embedded sensors
Author(s): Peter H. Møller, Oskar Klinghoffer, Erik Stoltzner
Paper category : conference
Book title: 2nd International Symposium on Service Life Design for Infrastructures
Editor(s): K. van Breugel, Guang Ye, Yong Yuan
Print-ISBN: 978-2-35158-096-7
e-ISBN: 978-2-35158-097-4
Publisher: RILEM Publications SARL
Publication year: 2010
Pages: 485 - 492
Total Pages: 8
Nb references: 3
Language: English

Abstract: To concrete structures several reasons can make it advantageous to extend the typically design service life of 50 to 100 years (or postpone the time to extensive repair):
_ Financial benefits of postponed investments (3-7 %/year of the construction costs).
_ Better possibilities to adapt the bridge for future traffic requirements
_ Longer service life reduces environment impact

Usually concrete structures are renovated or replaced before the deterioration process has gone very far. However, in order to extend the lifetime, it will usually be necessary to wait until the later stage of the deterioration process called propagation phase. During this phase the condition of the structure can change very fast, and therefore these conditions must therefore be monitored in detail. Monitoring of the important corrosion propagation phase can often profitably be done by corrosions sensors, since the normal most visual based monitoring method often will be costly and cause traffic delays. Often the possibilities for documentation of the current condition of the structure are determining the possibilities for lifetime extension, and the sensors can therefore have direct influence. For this use new sensors focusing on corrosion propagation were developed at late 90-ties and further matured and tested during a 12 year test period.
This paper describes why extension of the lifetime is important and how sensors together with the more usual methods for monitoring the condition of the structure can improve the possibilities for extended lifetime. The first application of specially designed corrosion sensors is described through field experience from a 220 meter long highway concrete bridge, bound for demolishing. From detailed determination of the construction strength followed by extensive conditions monitoring, demolition of the bridge could be postponed for 12 years.
This postponement resulted in cost savings of approx. 15 million €. During demolition of the bridge in 2010 it will be verified if the real condition of the structure could be evaluated by results from the sensors.

Online publication: 2011-04-20
Publication type : full_text
Public price (Euros): 0.00