Three kinds of failure modes for perfobond rib shear connectors with perforated rebar are summarized from previous tests

and it is found that the shear failure of perforated rebar gives full play to the ultimate bearing capacity.In order to study the influencing factors of the ultimate bearing capacity of connectors

21 specimens of perfobond rib shear connectors

sorted into 4 groups

are tested in the fracture test

and the test results in reference are also referred.A calculation formula of ultimate bearing capacity for perfobond rib shear connectors is established.The results show that the size and strength of perforated rebar significantly influence the ultimate bearing capacity of perfobond rib shear connectors with perforated rebar

which is unrelated to the size and strength of concrete rebar.The ultimate bearing capa-city is also related to the size and strength of transversal rebar

which is less significant than that shown in these existing formulas.