Abstract
In this paper, the M-N-φ relationship of a beam section and the calculation of deformation for the externally prestressed tendon with large eccentricities are studied. A general method for analyzing the stress increment of external tendon and beam flexural behavior is presented. In this method, the action of external tendon is expressed as the equivalent loads applying at the deviators and anchorage ends. The beam not including external tendon is subjected to bending moment and axial force caused by both applied loads and equivalent loads. By comparing the different positions of deviators and anchorage ends before and after loading, the force of external tendon is obtained, the deformation compatibility of the external tendon is met, and the loss of tendon's eccentricity can be considered automatically. The calculation results conform well to the experimental results in reference [1].
