Neutron engineering application for structural engineering of reinforced concrete structure

Suzuki, Hiroshi  ; Kusunoki, Koichi*; Kanematsu, Manabu*

In the modern society, architectural and civil engineering structures such as reinforced concrete buildings require high seismic performance to minimize the risk exposed from urban earthquake hazards. In the reinforced concrete structures, the bond resistance between rebar and concrete is one important parameter for discussing the bond condition, and typically evaluated by measuring the strain distribution along the embedded rebar. In this study, the time-of-flight neutron diffraction technique was applied to the strain measurement of the rebar embedded in concrete. The three-dimensional deformation behavior of the embedded rebar including the axial and transverse strains was accurately measured under pullout loading. Furthermore, bond deterioration around the cracks in concrete and that around corroded rebar were successfully observed by measuring the strain distributions along rebar by neutron diffraction. The neutron diffraction technique is expected to be a novel strain measurement method for the rebar embedded in concrete for understanding actual phenomena on reinforced concrete structures.