Strip and bar WIM Sensors
Strips and bars WIM sensors are installed in grooves made in the upper pavement layer and fixed with epoxy resins. Both the manufacturing and installation cost are reduced compared to the scales. The typical dimensions of a bar are: 3 to 4 cm (width and height) and the length vary between 0.75 to 1 m for a half lane (wheel weighing) or 3 to 4 m for a whole lane (axle weighing). They are mounted in grooves of 6 to 8 cm in depth and width. A strip is flat (below 2 cm in height) and 3 to 5 cm in width. Both strips and bars contain sensitive elements, capacitive, piezoelectric, strain gauges or fiber optics sensors, which measure pressure or strains variations while a wheel or an axle is passing on them. Strips and bars are mainly used for HS-WIM.