The International Information Center for Structural Engineers

Non-contact mechanical tension measurement in prestressed concrete structures

P. Obluk,P Fabo,J. Tkáč.
Book Title or Journal
Procedia Engineering, Vol.65
Number of pages
pages 273-277
INSET company developed a unique measurement system DYNAMAG® which allows non-contact mechanical tension measurement in prestressed steel parts of concrete constructions like beams, plates etc. Principle of measurement method is based on the magnetoelastic effect of ferromagnetic materials. There is an interaction between the magnetization and the strain of a magnetic material. DYNAMAG® measures the change of relative permeability of the material during its mechanical load. DYNAMAG is suitable for both checking the quality of prestressing process during construction and for long term monitoring. Typical applications are: • in geotechnical structures like tunnels, anchored pile walls, and embankments (tension measurement in ground anchors) • in bridge structures for monitoring prestressed beams and plates, cable-stayed bridges and extradosed bridges (tension measurement in steel strands, cables and rods)