| Since 1980s', carbon fiber reinforced polymer (CFRP) has been used to strengthen buildings. As so far, a great deal of experiments have been carried out at home and abroad, which promote its application in the field of structural reinforcement. However, there are few papers emphasize on slab-column connection reinforced by CFRP, the theory is lag behind the development of slab-column structure. In view of this situation, on the basis of references, a series of experiments are conducted to strengthen slab-column connection by using CFRP. Strengthening method, mechanical properties, failure modes, and related theoretical calculations are studied.There are five slab-column connection specimens (A2, A4, A6, A8, A10) need to be restored, which are damaged in varying degrees. These specimens are loaded with vertical force combined with unbalanced moment formerly, punching shear failure occurre for the A4, other specimens'steel reached yielding and concrete crack, which can be considered as moderately impaired state. After upgrading by externally install CFRP stirrups, these specimens are tested under constant gravity shear and lateral displacements are applied in a reversed cyclic manner. The strain of steel, CFRP, and flexivity are collected in the process of experiment. Compared with control specimens, the results of the experimental program show that shearing bearing capacity and deflection increase by 24.3% and 49.4% respectively, and the lateral drift-ratio could meet building code requirements. Furthermore, according to the failure pattern, the calculation method for upgraded specimens is put forward, the ratio of trial value and calculated value is 1.43, the calculation results are reasonable and safe. In summary, the result of experimens show that upgraded specimens have significant improvements of ultimate load carrying capacity, seismic behavior, as well as failure pattern.
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