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Retarding mortar which meets the requirements of the bonded post-tensioned prestressed concrete is developed. 12 retard-bonded partially prestressed concrete (P. P. C) T-beams are tested. There are two kinds of loadings, one is static loading, and the other is constant-amplitude fatigue loading. The strain increment of reinforcement and concrete, crack width and deflection versus number of cycles under constant-amplitude fatigue loading are obtained from the test results. In addition, the conclusion is drawn that the damage of P. P. C beams is due to the fracture of non-prestressed reinforcement. Compared with the T-beams in the same conditions except job practice, fatigue life of retard-bonded P. P. C T-beams is much longer. Based on the test results, the formulas for prestress loss and fatigue calculation of P. P. C T-beams are recommended, and the calculating results match with the test results well. [ABSTRACT FROM AUTHOR]