Strainstall UK Ltd are world-leading specialists in load measurement and stress analysis with more than 40 years of experience across all engineering disciplines. They have many years of experience in the railway industry, and have developed a specific range of produces and services that are widely used by infrastructure and rolling stock managers to assist with monitoring and stress determination.

At Railtex 2004 (stand number 843), Strainstall will be demonstrating TrackAlert®, a system which identifies wheel defects and vehicle weights through dynamic monitoring of existing bridges. Instrumentation is fitted under the bridge, effectively turning it into a weigh-bridge. A combination of special strain sensors and accelerometers with real-time data processing enables axle loads, axle overload problems and wheelset ‘flat spots’ to be measured. There is also the option of providing rail vehicle identification via digital photography, vehicle tagging or real-time integration with other information systems such as CIS, TRUST and TOPS. TrackAlert® can be extended to provide a road vehicle impact detection system, or the standalone Bridge StrikeAlert, the latest version of which will be shown at Railtex.

BridgeStrikeAlert involves the instrumentation of a bridge to obtain dynamic shock measurements. In the instance of a bridge with multiple decks, each deck can be independently monitored along with collision protection beams (CPBs) if fitted. This ensures that in the event of a strike by a road vehicle, a rapid assessment can be made as to whether a CPB only has been struck and / or which deck. Depending on local procedures, this information can then be used in the decision making process as to individual lines being kept fully open or trains cautioned. Having this type of information immediately following a bridge strike can clearly play a key role in reducing the delays to both rail and traffic. An optional camera system is also available that gives additional support information such as the type of vehicle involved and whether it is stuck under a bridge, and which can be utilised to peruse compensation claims.

Strainstall also provide structural monitoring systems, which start from the simple installation of a few strain gauges, to complex systems comprising many different sensor technologies and real-time data processing. They regularly undertake static and dynamic load testing on bridges, structures and rolling stock and in-situ stress determination to measure residual stresses and / or dead load stresses through a variety of stress relief techniques.

The company also supply load cells and instrumentation, including the ‘Points Pin’, which is a specially designed load measurement pin to fit both electric and hydraulic switch mechanisms, providing a means to monitor point operation force as a tool for improved asset management or as a pre-warning of points failure. In addition, their support team is available to carry out strain gauge installation and testing, as well as experimental stress analysis reporting to assist in the design verification process.