Structural monitoring of Beirut silos
The Beirut Grain Silos, 42 cylindrical reinforced concrete structures 48 meters high containing 85% of Lebanon’s grain reserves, was built in the port of the capital in the late 1960s. On August 4, 2020, the tremendous explosion that occurred in the warehouse of storage just 85m away from the Silos caused enormous damage, impacting the city along a 600m radius. The part of the structure facing east collapsed completely, while the one facing west resisted without collapsing, preventing the shock wave of the explosion from reaching the western part of the city with all its original strength.
The Beirut grain silos therefore partially protected the city of Beirut from destruction, despite being only a few tens of meters away from the heart of the detonation. Thanks to this huge contribution to the city, this structure has become a symbol for the whole of Lebanon.
A few months after the catastrophic event, after the 3D laser measurements of the end of 2020 and the spring of 2021, inclinations that were not visible without adequate instrumentation were highlighted. For this reason, the Swiss company Smartec was able to deliver to its customer, Amann Engineering GmbH (Geneva CH), a wireless sensor system from Move Solutions for the permanent monitoring of the Beirut silos.
The monitoring system consists of multiple Triaxial Tiltmeter sensors, installed tens of meters high to monitor any angular variation of the inclination of the structure. These wireless devices are very easy to install and therefore are perfect for a dangerous and difficult-to-access facility like this one. The entire monitoring system uses LoRaWAN radio communication to send the detected data to the Gateway installed on site. These Triaxial Tilmeter by Move Solutions, installed on the walls of the Silos, allow monitoring these rotations imperceptible to the naked eye with high resolution and precision correlating it to a temperature measurement.
The collected data can be viewed in real-time thanks to the Move Cloud Platform, which allows the customer to remotely monitor the site of interest and, through the many tools available, facilitates its analysis. With the Move Cloud Platform, the customer was able to set different operating parameters for each sensor, including sampling rates, alarm thresholds and much more.
The system guarantees constant monitoring of the health of the structure and the creation of historical records of the collected data which can be accessed at any time.