Remote monitoring of protection structures and moving slopes: a sensor and dashboard set-up that records impact and movement events and notifies when a threshold is exceeded. The aim is to reduce the number of inspections and shorten the time spent in the hazard zone.
The problem
Once a protection structure is installed, the question does not end, it changes: is this system still able to do its job? A barrier may have caught a block and its brake may have opened; a debris flow barrier may have filled up; movement in a slope may have accelerated. None of this is seen without a site visit, and a visit is both expensive and time spent in the hazard zone. On lines that cannot be reached in winter, the condition of the system is unknown for the whole season.
The questions monitoring answers are limited and clear: did an event happen, when did it happen, how much was the structure loaded, is the movement accelerating, when is the next inspection needed. Monitoring is not a prediction machine; it tells you that movement is accelerating and that a threshold has been exceeded, and a person makes the decision. When this distinction is not set from the start, things are expected of the system that it cannot deliver, and trust is lost.
How we decide
The data we measure and set: the type of structure or mass to be monitored, event frequency, the expected speed and direction of movement, the required response time (road closure, evacuation), accessibility and seasonal closure, network coverage, power source, who receives the data and what that person will do.
| Observation | Criterion | Decision |
|---|---|---|
| Long barrier line with difficult access | Inspection cost high, events seen late | Rope-mounted monitoring device: impact, rope force and corrosion; event notification |
| Debris flow barrier, filling unknown | Emptying time is missed | Filling and event detection, together with rainfall data |
| Measurable movement on the slope | Displacement rate changes over time | Displacement and tilt measurement, threshold alarm |
| Movement present but rate unknown | No baseline measurement to compare with | Baseline period first, threshold set afterwards |
| An alarm will trigger an action | Road closure, evacuation, work stop | Threshold, responsible person and procedure defined in writing |
| No network and no power | Data cannot be transmitted | Independent power and alternative communication, or on-site logging |
Choosing the threshold is the core of this work. A low threshold produces constant false alarms and after a while nobody looks; a high threshold misses a real event. The right method is to measure the baseline noise over an observation period and derive the threshold from that data. Wind, passing animals, vehicle vibration and temperature change are known sources of baseline noise.
System family
| System | When suitable |
|---|---|
| Event detection device fitted to the barrier rope | Impact and loading on rockfall, debris flow and avalanche barriers |
| Tilt and displacement sensors | Monitoring moving masses and slopes |
| Rainfall and weather measurement | Monitoring debris flow and landslide triggers |
| Dashboard and notification | Making the data readable and notifying threshold events |
| Device installation, site set-up and commissioning | Installation, calibration, threshold setting |
A rope-mounted event detection device can be chosen separately from the barrier manufacturer. Geobrugg GUARD is installed on steel wire ropes of 12–24 mm diameter; on another manufacturer's barrier the documents are reviewed first and the written opinions of the barrier manufacturer and of Geobrugg are obtained. If the conditions are met, a route equipped with different systems in different years can be monitored from one dashboard. Device life, battery life and protection class vary by product; they are written in the quotation file in years and as the protection class.
Installation
Installation is short but preparation is long. First the monitoring purpose and the action tied to the threshold are written down: who will be notified, what they will do, where the record is kept. Then network coverage is measured on site, device positions are fixed, the installation is done and a controlled alarm test is run at commissioning. During the baseline period the threshold is kept provisional and is finalized at the end of the period.
Checkpoints: device position and orientation, connection torque, coverage measurement, verification of the data flow to the dashboard, testing of the notification list, consistency of time stamps, who owns the data and where it is backed up. Access to the devices on the ropes is by experienced specialists on rope access.
Acceptance and maintenance
Measured at handover: list and positions of installed devices, coverage measurement record, the first data reaching the dashboard, the alarm test record, threshold values and their justification, the list of people who will be notified, the data storage and access arrangement. Who may change the threshold is also written down; a threshold raised quietly leaves the system useless.
In maintenance: monitoring the power status, checking for data gaps, repeating the notification test at the start of each season, corrosion checks, comparing actual events with site observation. The last item matters most: each warning is compared with the situation on site; where they do not match, the threshold or the device position is reviewed.
Frequently asked
- Does a monitoring system know about an avalanche or a rockfall in advance? No. It detects the event, records the loading and, if the movement is accelerating, notifies when it exceeds the threshold. What it is for: what a monitoring system is for (Turkish).
- Can it be fitted to another brand's barrier? Yes, if the conditions are met. Geobrugg GUARD is installed on steel wire ropes of 12–24 mm diameter, and its tightening and placement rules also apply. First the barrier's documents and its condition on site are reviewed, and the opinions of the barrier manufacturer and of Geobrugg are obtained in writing. Together with document review, ID tag and inspection plan on an existing line: rockfall barrier monitoring.
- What happens when an alarm comes in? The action must have been written at installation: who is notified, at which threshold the road is closed, when the inspection team goes out. The steps after an impact: what to do after an impact (Turkish).
Field record
1 project in this family in our records, 2026: Türkiye. Under confidentiality agreements, project and client names are not published.