Focus on Structural Health Monitoring of bridges
ElastiSense have found the key to efficient structural health monitoring of bridges and other engineering structures
The main purpose of structural health monitoring of engineering structures is safety and economy. The condition of civil infrastructure systems changes over their life cycle, typically due to damage, overloading, environmental inputs, and aging. By monitoring the structures, predictive maintenance becomes an option, which can prevent damage or even collapse.
If you are able to continuously monitor the structure on a bridge and know in what state it is, you are in control of the maintenance costs and thus able to be proactive on maintenance and safety issues. Poor maintenance of bridges has historically led to catastrophic bridge collapses. One of the latest examples is the Ponte Morandi motorway bridge collapse in Genoa, Italy, killing 43 people.
The value of structural monitoring is clear, but objective condition assessment and performance evaluation are still challenging activities. They require some type of monitoring to track the response time. Some of the challenges preventing structural health monitoring on a larger scale include the costs of monitoring systems, where most existing systems are quite expensive. They also include questions regarding which type of sensors to use. The issue of finding sensors capable of performing reliably in all types of weather is dominant. On top of that. the installation of the systems is often time-consuming, labor-intensive, and expensive.
DS-Series Displacement sensors from ElastiSense are the keys to increased safety and decreased maintenance costs in bridges and other engineering structures. DS-Series sensors are developed especially for harsh environments, including outdoor settings where they will be exposed to rough weather.
On bridges, DS-Series sensors have historically been used to measure the movement of joints, bearings, suspension, the relative distance between the abutments and the seat of the bridge, or cracks in the structure.
DS-Series displacement sensors are superior to alternative sensor solutions when it comes to structural monitoring of bridges, because they consist of an innovative, extremely strong, durable, and very efficient stretch sensor, fully encapsulated in high-grade silicone rubber and with embedded electronics. This makes them extremely durable and completely resistant to external influences such as rain, snow, dust, heat, cold, dirt, and other environmental and weather-related obstacles. Furthermore, the stretch sensor technology combined with the silicone rubber encapsulation, makes them bendable in all directions and tolerant to over-stroke and misalignment. The technology is unique for ElastiSense products and provides a superior alternative to non-contact or cylinder-based sensors, which have traditionally been used for structural health monitoring. Installation is easy and the sensors require no maintenance. They can sit there for years and continuously deliver data about the status of the bridge.
ElastiSense has had great success in several cases with structural monitoring of bridges. The Norwegian Road Directory (Statens Vegvesen) has, for example, mounted two DS-Series sensors on a bridge in Norway. Learn more about that project here: https://elastisense.com/news/ds-series-displacement-sensors-bridge-monitoring. These sensors measure the relative displacement between the abutments and the seat of the bridge. In bridges like the one in Norway, displacement is usually caused by changes in temperature and load variations. Precise data about the displacement is essential to be able to foresee wear and tear, fatigue, and potential crack generation on the bridge. The overall purpose is to enable preventive measures and perform predictive maintenance on the bridge.
In Southern Denmark, another bridge monitoring case has shown the value of DS-Series sensors. In this case, Rambøll, KI Consulting Engineers, and Sønderborg Municipality have joined forces and installed sensors on the “Munkemølle Bridge” dating back to 1935. Learn more about that project here: https://elastisense.com/news/bridge-monitoring. The purpose of this project is to determine what state the bridge is in, and based on that, decide which maintenance initiatives to engage in. In essence, Sønderborg Municipality needs data to essentially make the best decisions regarding economy and safety. Instead of doing expensive difficult service checks several times a year, it makes perfect sense to continuously monitor the bridge with sensors.
Both the abovementioned cases are examples of the new sensor technology from ElastiSense, being used to increase safety for bridges and reduce maintenance costs. It appears that ElastiSense, with the DS-Series displacement sensors, has cracked the code to efficient and valuable structural health monitoring of bridges and other engineering structures.