Computation of the Strand Resistance Using the Core Wire Strain Measurement

Keunhee Cho, Sung Tae Kim, Sung Yong Park, Young-Hwan Park

Structural System Research Division, Korea Institute of Construction Technology, Goyang-Si, Republic of Korea.

DOI: 10.4236/eng.2013.511103                

Abstract

This paper proposes a method enabling to compute the prestressing strand resistance using the strain measured on only one core wire. Numerical analysis is conducted considering the pitch length of the strand and the diameters of the core wire and helical wires as parameters. The results verify that the relation between the stresses of the core wire and helical wires can be expressed in terms of the helical angle. Based on this observation, a formula computing directly the prestress force in the strand from the strain measured in the core wire is suggested. Owing to the recently developed measurement method for the core wire strain, the proposed formula can be exploited to determine the prestress of the strand.

Keywords

Finite Element Method; Measurement; Prestress; Strand; Core Wire; Helical Wire

Conflicts of Interest

The authors declare no conflicts of interest.

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