Fiber optic technology: broad and current understanding of structures

Monitoring systems using fiber optic technology are on a steady rise, also in construction. The discipline, better known as optical sensor technology (fiber optic sensing) is one of the activities of Brem Funderingsexpertise from Reeuwijk. With this, the specialist in the field of advice, monitoring and supervision for foundation engineering has embarked on a broader path to monitoring structures in general.

Text | Chris Elbers  Image | Brem Funderingsexpertise B.V.

When it comes to monitoring foundations and structures, Brem offers a complete program of (geotechnical) measurements. This focuses on the quality of foundations or structures, but also the mapping of any nuisance around their realization. "We represent a wide range of monitoring techniques that can be applied both separately and in complete monitoring networks," said Erik de Bruin, operational manager of monitoring within Brem. "One of them is monitoring via fiber. Brem uses two measurement methods for applications of this measurement technique. One is particularly suitable for monitoring the behavior of a construction, both static and dynamic. The other is specifically applied around long-term monitoring of phenomena within a structural assembly, such as deformation and temperature changes."

Install sensor cable underdeck.

Clear answer

With sensor technology, Brem provides a clear answer to a currently ongoing trend in the construction industry. De Bruin explains, "Contractors are not only responsible for realizing projects, they also need to be able to carry out maintenance for a longer period of time. A development to which fiber optic monitoring fits nicely, for example in the case of artworks. By incorporating sensor technology, you have continuous remote insight into how the structure is behaving. Traditionally, a maintenance protocol is drawn up, after which inspections are carried out once every quarter or six months. When you equip a structure with this technology, this is no longer necessary. You can simply see from behind your desk whether there is a change in strength or subsidence, for example. This gives you better insight into how the structure is behaving and, no less important, whether you will have to incur maintenance costs in the long run."

Advantages

Unknown makes unloved. In the case of sensor technology, it is already no different. Although the technology has been used in the construction industry for several years, it is still very little used. It is up to Brem to convey its many advantages and application possibilities (see also www.brem.nl). "This measurement technology will drastically change the future of building and rail/infra management," De Bruin believes firmly. "Simply because maintenance will take place based on information obtained from monitoring instead of predetermined intervals. On top of that, safety increases because the current state of the structure is immediately visible and demonstrable."

Protective structure sensors at expansion edge beam.

Reference project with optical sensors in Antwerp

In Antwerp, Brem recently completed a monitoring project in which optical sensors were widely used. By mounting the sensors on the reinforcement steel and pouring them into the concrete, they are optimally protected and information is continuously obtained about the strength and possible deformation of the structure. This is a concrete structure in a busy rail infrastructure. The solution is equipped with an online data dashboard including the necessary alarms and will provide the customer with the necessary information for a period of at least 10 years to ensure safe use of the structure.