Nizar Lajnef
- Associate Professor
- Civil and Environmental Engineering
- PhD, Civil Engineering, Michigan State University
- MS, Civil Engineering, Michigan State University
- 428 S. Shaw Lane, Room 3546
- Engineering Building
- East Lansing, MI 48824-1226
- 517.353.8883
- lajnefni@msu.edu
Links
Using the Mackinac Bridge to test sensor technology
Current Research
The next generation smart cities will be heavily dependent on distributed smart sensing systems to monitor the urban infrastructure. One of the main challenges in structural health monitoring (SHM) is to find a reliable and suitable source that can continuously power the sensors during the whole life span of the built structural system (typically few decades). Traditional health monitoring systems rely on batteries which have a very limited lifetime, thus requiring frequent replacements. This is impractical and would considerably increase maintenance cost. Dr. Lajnef’s research, in self-actuated sensors has work led to the development of a battery-free, wireless multi-metric sensing system for the continuous and autonomous monitoring of bridge components. The sensor operates by harvesting mechanical energy from structures using piezoelectric transducers. The performance of this technology is benchmarked for different civil infrastructure systems subject to a multitude of damage scenarios. The developed models integrate finite element (FE), experimental testing, and statistical and artificial intelligence (AI) approaches. Sensors fusion models are also developed to increase the accuracy of the damage sensing system. As part of this research, a network of sensors has been deployed on the Mackinac Bridge.
Expertise
- Design and implementation of a smart continuous-monitoring system for asphalt and concrete pavement structures
- Design and implementation of a sub-microwatt self-powered fatigue sensor
- Sensors design for civil infrastructure and biomechanical systems
- Sensors networks design and implementation
- Nano-watt and self-powered sensors, and smart materials/composites/alloys and systems