Database Evaluation of Interface Shear Transfer in Reinforced Concrete Members

A database of interface shear-transfer experiments on uncracked reinforced concrete specimens was created from published test results. A total of 774 tests were reviewed, with data coming from tests conducted between 1969 and 2014. Once compiled, the database was used to evaluate the accuracy of the interface shear transfer provisions from the AASHTO LRFD Bridge Design Specifications, Eurocode 2, and CSA A23.3. Through this evaluation, it was determined that experimental capacities were an average of 1.49, 1.93, and 2.83 times greater than the code-calculated nominal capacities for the LRFD, Eurocode, and CSA codes, respectively. While each of the codes was conservative on average, the degree of conservatism was found to be dependent on design variables such as concrete compressive strength, amount of interface reinforcement, and member size. For example, conservatism of LRFD was lowest for specimens having concrete compressive strengths less than 60 MPa ( 87ksi). Conditions associated with the lowest degrees of conservatism are identified and discussed.