Strainstall is equipped to undertake dynamic response testing of structures, with its quick-to-mobilise equipment which can be easily set up on site.

Measuring displacement and vibration responses is a common requirement with bridge structures, and key parameters to be determined include displacement, frequencies of response and damping coefficients. Basic configuration includes linear displacement transducers and optional accelerometers fitted to telescopic poles. Raised to the soffit from ground level, they reach a maximum height of around 9 metres and are pushed into firm contact with the bridge in question. Other sensors, including strain gauges, can be incorporated, but may need special access arrangement for installation. 

The sensors are connected to a high speed data acquisition system, capturing data at a rate that is sufficient to enable the full dynamic characteristics to be measured. Our Strainstall engineering operatives are able to carry out analysis on the data as testing proceeds to confirm key parameters and system functionality. 

For rail bridge tests it is particularly important to record train details in order for the loading patterns to be correctly interpreted. Our site teams are skilled in train identification and employ the use of a video camera to record train events when required. 


  • Linear displacement transducers 
  • Accelerometers 
  • Displacement transducers 
  • Strain gauges 
  • Multi-channel, high-speed data acquisition system 


  • Rapid installation and set-up 
  • Data analysis as trials proceed 

Projects include: 

  • Over 80 bridge resonance tests for the West Coast Route Modernisation project, from initial studies to verification tests involving the C390 test trains 
  • Motorway, under-bridge deflection measurements for assisting in the determination of a safe method for welding as part of a strengthening scheme 
  • Deflection measurements to assist in structural assessment (CTRL scheme) 


Download Strainstall's Deflection, vibration, strain monitoring case study.