Filtern
Dokumenttyp
- Vortrag (6)
- Beitrag zu einem Tagungsband (3)
- Zeitschriftenartikel (1)
- Posterpräsentation (1)
- Forschungsbericht (1)
Sprache
- Englisch (12)
Schlagworte
- Concrete (12) (entfernen)
Organisationseinheit der BAM
Eingeladener Vortrag
- nein (6)
This working paper summarises the current state of knowledge and research on the application of sensors in road pavements, designed to record input quantities and characteristics for structural assessment. In this working paper, sensors generally refer to technical equipment that can used to record the values of physical quantities and display them for interpretation.
The working paper deals with every type of sensor that is permanently connected to the road, i.e. sensors that are installed – in the bound and unbound courses of the superstructure as well as in the sub-base/sub-structure, – next to or above the road (for example on masts) and can contribute to structural recording and its subsequent assessment. This can also include sensors that are primarily used for a different purpose (e.g. traffic control). However, this working paper only describes the application of sensors that are installed primarily for other purposes for the sake of completeness; special publications (e.g. Notes on detection technologies in road traffic) are available for the respective installation situations.
Structural Health Monitoring (SHM) has become very important in today's rapidly developing time. High buildings, large bridges and complex technical structures need to be monitored continuously and this over long periods.
Visual monitoring cannot evaluate the internal condition of building structures. Thus, material embedded sensors are needed. Cable connection of these sensors pose the disadvantage of weak spots and water intrusion. For concrete embedded sensors the use of batteries is not convenient, because of limited lifetime, difficult charging, and generation of electrical waste.. Hence, monitoring should be implemented preferentially with firmly embedded passive RFID sensor modules. However, since the concrete structure forms an electromagnetically reflective and absorbing barrier, only limited energy can be transmitted to the module. This project requires a highly energy-saving system, which can record different sensor parameters at critical points.
One of the more difficult tasks for structural health monitoring is the continuous evaluation of the stability and load capacity of the building materials. This knowledge can be won, e.g., by taking material samples at the examining place with the drawback of partly destroying the structure. To avoid this, modern sensor and communication technologies offer promising methods for non-destructive testing. To address the tasks for monitoring of concrete structures, in the presented study, different sensors were combined with RFID transponders and embedded in concrete components.
Moisture testing and mapping
(2018)
Damages in infrastructure due to moisture amount to billions of Euros every year. For a more predictive structural health monitoring in civil engineering, the detection and monitoring of hazardous moisture in steel reinforced concrete constructions is of high interest. The sensors have to be wireless, elsewise they weaken the concrete cover of the rebars. The lifetime of such constructions is normally decades, thus the sensors have to be battery-free and fully passive. Considering these requirements, passive RFID-based sensors are developed. Communication and energy supply are realized wireless via the electromagnetic field of a RFID transmitter. The passive RFID based sensors are embedded into the concrete to enable the monitoring of moisture transport in porous materials. Results of the hydration process are shown.
Moisture testing and mapping
(2017)
Moisture testing and mapping
(2017)