Monitoring system for bridges

Fiber optics products can be used to monitor the condition of different bridges; it evaluates in real-time depreciation during the exploitation, provides public safety, and cuts the expenses for maintenance.

Data collected by these fiber optics products allow decreasing regular maintenance expenses of the constructions. All the information is stored in an orderly manner to enable sorting through long and short-term tracking periods. Using a monitoring system helps to use the facility in a more efficient way. Monitoring fiber optics products help to build the construction and to optimize the load in different situations, and it will make the utilization time.

The following parameters are measured with fiber optic product:

  • Relative linear beam deformation
  • Temperature next to the deformation place
  • The inclination of the supporting structure
  • Other physical dimensions

Beam sensors are located on the right and left sides of the bridge and the fiber optic product controls the pressure on the entire length of the construction, bridge conditions during the peak load and at relaxation time, relative changes in different structure elements during the exploitation period, climate changes effect.

Fiber optic product for inclination tracking controls the potential shift of the bridge over time. And the fiber optic product located at the central part of the bridge tracks the vibration and the danger of resonating frequencies.

The amount of sensors per bridge is always determined case by case. In general, it depends on the central part between the supporting structures. The part that takes the heaviest load is the central part of the bridge and it has to be measured precisely.

These sensors help to find weak parts of the structure and prevent damages and catastrophes.

Dynamic Cable Rating

In recent years a lot of research has been done in order to increase the power flow of underground cables and to develop the equipment to effectively monitor the weather and thermal state of the cable by creating accurate thermal models. As a result of applying dynamic thermal rating technologies, the capacity is usually increased by 5 to 15%. Few factors determine the thermal rating of the underground, among them the soil temperature and thermal resistivity of the earth, and they change very slowly, don’t get affected much by weather and current loading.

The main challenge with underground installations is to accurately measure the maximum current value that can flow through the circuit breakers.

The current capacity carried in specific cable circuit breakers depends on certain aspects, such as cable construction, the soil, the temperature, and the sheath-bonding method. Only the soil properties are variable, and the others are constant.

The soil is affected by the weather change in different seasons and the cable heating, hence the current carrying capacity changes drastically. Dynamic current rating of a cable circuit is a crucial factor in order to utilize it in the full capacity all year round; because it is always the biggest challenge for power operators to choose the right power load for the underground cable.

That is why monitoring thermal conditions of the buried cable circuits and installed distributed temperature sensing (DTS) systems is crucial.

A real-time operating system is created to capture different load current parameters, cable surface, and soil temperatures to provide input to the real-time operating system. The data about current and temperature is passed to a computer through the fiber optic connection. The computer gathers load and temperature data and provides an updated ampacity rating.

Once the dynamic current rating data is received, it has to be analyzed within a set period of time. The results are usually used to develop risk management strategies. There are certain challenges when calculating line ampacity, such as conductor properties and atmospheric conditions, which have to be considered. Each of these factors increases the level of uncertainty when determining ampacity.