Abstract: Through the experiments on the flexural behaviors of 10 pieces of T-beams， the influence of different prestress degrees， numbers of strengthening layers of CFRP as well as the pre-splitting degree on the load， midspan deflection and ductility factor of T-beams strengthened by the combination of CFRP and steel plate were studied. The results showed that the ultimate load P_○u of the strengthened T-beam is over 90% higher than that of the comparison beam. The impact of prestress degree on the ultimate midspan deflection f_○max and the ductility factor μ is obvious in such a way that the f_○max reduces about 25% when the prestressing force increases 5%. The yield load P_○y and the ultimate load P_○u increase linearly with the increase of the strengthening layers， and decrease linearly with the increase of the pre-splitting degree. The P_○u of the T-beam strengthened by three-layer CFRP increases 52.8% than that strengthened by one-layer CFRP. When the pre-splitting degree is 60%， the f_○max reduces about 10%.

Key words: reinforced concrete T beam, prestressed CFRP, steel plate, combination strengthening, flexural behavior