Feasibility Study of Measuring the Stress in Prestressing Tendons Using Induced Magnetic Field
نویسندگان
چکیده
This paper investigated experimentally the feasibility of the method to estimate the stress in the prestressing tendons of prestressed concrete bridges using the magnetic field induced by a moving electromagnet. This method is based on the Villari effect in which the magnetic permeability of prestressing tendons changes when subjected to a mechanical stress. The test results show high linearity between the stress in the prestressing tendon and the induced magnetic flux density within the practical stress range of the tendons. In addition, the induced magnetic flux density in the tendon depends on the intensity of the electromagnet, the distance between the electromagnet and the tendon, the presence of other ferromagnetic materials such as rebar and metal sheath.
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