Dynamic slant shear bond behavior between new and old concrete

Quasi-static slant shear bond behavior of new-to-old concrete interfaces has been extensively studied. However, the interfaces might be subjected to dynamic loading during their service life. Therefore, this paper presents an experimental investigation to assess dynamic slant shear bond behavior between new and old concrete. The split Hopkinson pressure bar (SHPB) was employed to apply dynamic compressive loads to slant shear specimens. Quasi-static slant shear tests were also conducted for the purpose of comparison. Test results show that the strain rate has significant effects on failure modes, bond strength, absorption energy and interfacial cohesion and friction angles of specimens. The energy absorption capacity of a specimen in the quasi-static test can be regarded as the threshold in the SHPB test, beyond which the specimen is damaged. Failure modes and bond strength of specimens are influenced by the slant angle but not by the surface roughness and the age of interfaces. (C) 2019 Elsevier Ltd. All rights reserved.