|Structural Health Monitoring (SHM) is the process of implementing a damage detection and characterization strategy for engineering structures in order to maintain the system’s performance. The SHM process involves the observation of a system over time using periodically sampled response measurements from an array of sensors, extracting damage-sensitive features from these measurements, and performing statistical analysis of these features to determine the current state of system health.
Over the long term data analysis increases visibility into the ability of the structure to perform its intended function. After extreme events, such as earthquakes or blast loading, SHM is used for rapid condition screening and aims to provide reliable, real time information regarding the integrity of the structure. SHM can be applied to fixed infrastructure, such as building and bridges, or mobile infrastructure, such as airplanes and trains.
Health Assessment of Engineered Structures of Bridges, Buildings and other related infrastructures:
Commonly known as Structural Health Assessment (SHA) or SHM, this concept is widely applied to various forms of infrastructures, especially as countries all over the world enter into an even greater period of construction of various infrastructures ranging from bridges to skyscrapers. Especially so when damages to structures are concerned, it is important to note that there are stages of increasing difficulty that require the knowledge of previous stages, namely:
1) Detecting the existence of the damage on the structure
2) Locating the damage
3) Identifying the types of damage
4) Quantifying the severity of the damage
It is necessary to employ signal processing and statistical classification to convert sensor data on the infrastructural health status into damage info for assessment.
SHM System's elements include:
- Data acquisition systems
- Data transfer and storage mechanism
- Data management
Data interpretation and diagnosis:
1) System Identification
2) Structural model update
3) Structural condition assessment
4) Prediction of remaining service life
An example of this technology is embedding sensors in structures like bridges and aircraft. These sensors provide real time monitoring of various structural changes like stress and strain. In the case of civil engineering structures, the data provided by the sensors is usually transmitted to a remote data acquisition centres. With the aid of modern technology, real time control of structures (Active Structural Control) based on the information of sensors is possible
Key vendors: Campbell Scientific, National Instruments, SENSeOR, SmartPatch