Location: Old Gotthard Track, Switzerland
Installed: 2023
Focus: Real-time detection on vertical rockfall fencing over tunnel entrances

Overview

Some segments of Switzerland’s Gotthard railway corridor pass through exceptionally steep terrain where traditional protective measures are difficult—if not impossible—to install. One such section required the construction of a 90-degree vertical rockfall barrier, positioned directly above a tunnel entrance.

The goal: to stop falling debris before it could reach the tracks below. But the vertical nature of the installation introduced complex safety and logistical challenges—both during setup and ongoing maintenance.

Installation Challenges

Working at this angle, above live track and power lines, required a high level of safety planning and coordination with SBB. Key concerns included:

• Avoiding dropped equipment that could strike overhead electrical lines

• Ensuring no installation components (e.g., pull-out cables) came into contact with live infrastructure

• Navigating extremely limited access, requiring workers with certified climbing licenses

To mitigate risk, a full security concept was developed in collaboration with SBB, outlining emergency procedures and structural planning.

Monitoring System Design

Sensors were installed directly on the steep barrier to detect any rockfall events that might impact the structure. Despite the compact footprint, the system is able to relay real-time alerts if debris strikes the fence.

Key features include:

• Rockfall impact detection using energy sensors

• Communication relays installed to bypass terrain obstructions

• Data delivery to operators and control centers for immediate response

Why a Vertical Barrier?

At this location, traditional catchment zones or downslope fencing were impossible due to:

• A stone wall directly behind the track

• A lack of any accessible ground space above or below

• The tunnel portal being flush with vertical mountain face

As a result, this steep-angle barrier is one of only a few of its kind, and represents a highly specialized engineering and monitoring solution.

Current Status

The system has been live since 2023 and continues to provide hazard detection along one of the Gotthard line’s most exposed points. It operates in coordination with adjacent monitoring systems to create a multi-layered safety network throughout the region. For more information about INGLAS & the Impact Sentinel system, contact us below.