Electro Automation have installed a Bridge Weigh in Motion (B-WIM) & Weigh In Motion (WIM) system for Queen’s University Belfast, University College Dublin and University of Alabama. It is the culmination of many years development in WIM using piezo electric sensors to detect weights.

This Weigh-in-Motion installation is being used as part of a joint research project between Queen’s University Belfast, University College Dublin and the University of Alabama. The main objective of this research was to accurately detect axle loads and position by developing a new generation B-WIM system.

B-WIM uses an existing bridge as a weigh scales to weight the vehicles as they pass overhead. This requires a system of sensors which can be easily installed on the underside of a bridge and these results are used to determine the axle weights, axle position, vehicle calls and speed.

This new B-WIM being developed will have the advantage of keeping lanes and roads open on busy carriageways avoiding major traffic disruption. The data collected can also be used for the enforcement of overloaded trucks and as assessment information for the Structural Health Monitoring (SHM) on the bridge and pavement assets.

This modern WIM installation on site is being used as the vital reference tool for developing this new B-WIM system. Electro Automation installed this equipment in road pavement approaching the research bridge, with the communications cabinet and equipment at the roadside.

The installation took place on the main Dublin/Belfast corridor on the A1 in Loughbrickland Co. Down. As this is a busy section on the M1/A1 corridor between Dublin and Belfast night works only were permitted and with partial lane closures.

Two lanes of the carriageway are continuously monitored and CCTV video is also provided. Piezo Electric sensors are used for weight measurement, loops are used for vehicle classification and the lane configuration is piezo-loop-piezo. A temperature probe is also installed.

The sensors & loops are connected to a WIM outstation in a nearby enclosure. The data acquisition and video equipment is housed here. Wireless communications is setup to allow Queen’s University personnel live access to the site data. Data is then downloaded remotely to the university as required.

The system was put straight into operation the night of the installation and was left to gather data before calibration took place.

The project is providing foundation knowledge which could likely lead to a working latest generation of portable B-WIM system available for use in USA, Europe and Worldwide. The research is also facilitating a PhD Masters research project.

Facilitating new technology to enhance road safety and road network management by monitoring the weights and volumes of traffic and helping predict the stresses and “wear and tear” of the road network. Real traffic data can also be used for SHM and fed back into assessments.