illustrates the range of tendon eccentricities corresponding to the stress limits. It can be seen that the use of straight tendons with constant eccentricity from end to end of the beam may cause the stress limits to be exceeded. For post-tensioned tendons a parabolic profile will efficiently satisfy the stress limits both at midspan and at the supports. For pretensioned tendons it may be necessary to use a single harping point at midspan or double harping points at about the third-points of the span to obtain a satisfactory tendon