Displacement Transducer Case Study
To design a bespoke bridge monitoring system to measure the displacement on the joints for Turkey’s new rail tunnel – The Marmaray Project.
The Marmaray Project
- This 76.3km long tunnel is the deepest immersed tunnel in the World and is regarded as the foremost challenging infrastructure project in Turkey.
- The tunnel provides a direct link between Halkali on the European side of Istanbul, with Gebze on the Asian side.
- This modernised high capacity rail tunnel will carry up to an estimated 65’000 passengers per hour in 2015, increasing to a predicted 75’000 in 2025, saving commuters a 1 hour 15 minutes of travelling time*.
The Solution – AML/SGD Displacement Transducer
To do this we created a bespoke bridge monitoring system using 3 off 50mm stroke length AML/SGD displacement transducers, forming a triaxial measurement of each joint. The AML/SGD series of displacement transducers utilise strain gauge technology to convert the linear movement of the joints within the tunnel into an analogue electrical signal.
The AML/SGD series of displacement transducers were chosen for their excellent accuracy (0.1%), coupled with their high resolution and long-term stability, making them a perfect transducer for The Marmaray Project.
The 50mm higher accuracy AML/SGD linear variable displacement transducers were wired into a custom-made IP68 die cast enclosure. This IP68 enclosure housed 3 off SGA load cell amplifiers, protecting the amplifiers from moisture ingress. This provided the Marmaray team with an amplified signal enabling them to accurately monitor the displacement of the joints within the tunnel.
These SGA series of load cell amplifiers are capable of delivering highly stable, high speed, industry standard analogue outputs, such as 0-10Vdc or 4-20mA, from very low-level input signals and are available from stock.
LVDT.co.uk are proud to have been involved in such an important project for Turkey and we hope to continue to assist with new and existing projects through our new Turkish distributor Sentez. To contact our new Turkish distributor please go to their website www.sentezsistem.com.
To see our full range of LVDT’s. We are always looking for demanding and exciting new challenges so if you have a displacement transducer case study you wish to discuss with us, please contact our knowledgeable and friendly sales team today on +44 (0) 118 981 7339 or email us.