Detection of an embedded tube
In the concrete linings of tunnels empty plastic tubes are built in for wiring light and blowers. During the production of the concrete linings these tubes are fixed at the reinforcement. During concreting several of these tubes were moved by the flowing concrete and lost their positions. Only some of the lost tubes could be found by drillings, others which where pushed far out of the planned position could not be detected with that simple technique. Betontest detected all missing tubes utilizing ultrasound reflection technique so all tubes could be used and cutting of the linings for applying new tubes was avoided.