TELECOM TOWERS: MONITORING WIND SPEED FOR SAFETY AND STRUCTURAL INTEGRITY

Telecoms towers are permanently exposed to the weather, often in elevated places with constant wind. High wind speeds pose a risk when technical personnel climb the tower for maintenance or modifications. The wind can also affect the structural integrity of the tower itself over time.

Maintenance activities can be very demanding in the telecoms industry, since towers are often found in remote places and the technical staff must travel to the site. Technicians must then climb the tower to service its components and it may be necessary to suspend maintenance activities if the wind speed becomes too high. In cases where the technical staff cannot complete the task at hand due to unfavourable weather, another trip to the site must be scheduled so telecom tower maintenance can demand plenty of man-hours.

If the structural health of a telecom tower is monitored remotely, maintenance activities can be programmed based on tower conditions. This is much more efficient than scheduling regular site visits which in many cases only waste time and fuel. With condition-based maintenance, every site visit is productive.

IMPORTANCE OF WIND DATA IN STRUCTURAL INTEGRITY MONITORING

Telecom towers must be designed to bear three main types of loads:

• Communication equipment mounted on the tower.
• The weight of the tower itself.
• Wind loading, which can include both constant forces and oscillation.

The first two loads are known in advance since they are determined when the tower is designed and built. However, wind loading is variable and it can only be analysed if wind speed records are available.

Although the average wind speed is an important metric, it does not reflect two important conditions that affect telecom tower loading:

• Wind gusts, which have a much higher magnitude than the average wind speed, typically occurring in a matter of seconds.
• Wind turbulence, which is a main cause of cyclical loads and oscillation.

There are many wind monitors that only calculate the average wind speed and thus are not reliable when it comes to structural health monitoring. Choosing the correct monitoring system for your site is essential in order to track several metrics;

namely highest wind gust speed, average wind speed and turbulence intensity.

In addition; temperature, humidity and atmospheric pressure can add some valuable insight into specific site conditions.

WIND MONITORING AND MAINTENANCE OF TELECOMS STAFF SAFETY

When maintenance activities are being performed on a telecom tower, the wind must be kept under close watch. Human balance is normally affected at speeds above 23 mph, but keep in mind that ground-level wind speeds are lower than those experienced several meters above the ground when climbing a tower.

Suitable wind speeds for telecom tower work are also determined by the type of activity, for example, installation of comms dish or a technician carrying out routine maintenance checks.

The danger posed by wind gusts should never be underestimated. The magnitude of gusts can be twice as high as the average wind speed and consider that wind forces become four times higher when the speed is doubled. Weather forecasts can give you an idea of what to expect but they cannot match the reliability of on-site wind monitoring. A weather forecast does not reflect site-specific conditions, while providing no data about gusts and turbulence.

CONCLUSION

A reliable weather monitoring system can simplify infrastructure management for telecommunications companies, especially when they own many towers in remote locations. Wind measurements can compliment a structural integrity monitoring program allowing maintenance activities to be scheduled more efficiently, based on actual conditions instead of regular intervals. This approach saves on fuel and man-hours.

Wind monitoring is also very important when installing new equipment on telecom towers and during maintenance activities. With accurate wind data, management personnel can decide if conditions are safe for work, greatly reducing the likelihood of an accident.

WINDCRANE® offers a range of monitoring systems to the Telecoms industry from basic wind speed only through to full solar powered weather stations measuring wind speed, wind direction, temperature, solar radiation, humidity and atmospheric pressure.

Every WINDCRANE system comes with a cloud connected data service which provides live data via mobile phone for unlimited users and a back up of all historical data for use in downtime/health & safety reporting and also for providing historical wind and weather profiles of specific towers or sites.