This paper presents a review of literature relating to prediction of the stress in the tendons at ultim ate in continuous concrete members prestressed with unbonded tendons. Laboratory testing of such beams, conducted in Europe and North America in the last 30 years, is reviewed, and a comparison is given between test data and predictions of the tendon stress at ultimate according to the provisions in two codes of practice. Predictions from the equations given in current American and Canadian codes (ACI 3 18- 95 and CSA A23.3-94, respectively) are shown to be incons istent with the test data, and it is indicated that the pattern of loading is a parameter th at needs to be co ns ide red in predicting the increase in tendon stress at ultimate in continuous beams. Approaches adopted by recent investigators to account for this factor are outlined and discussed.
