A Study on the Non-Destructive Detection of Salt in Concrete Using Neutron-Captured Prompt-Gamma Rays at RANS

Abstract

We are studying the non-destructive detection of salt gradients in concrete using a neutron-captured prompt-gamma-ray analysis at the RIKEN Accelerator-driven compact Neutron Source (RANS). The neutrons at RANS are generated via a 7-MeV proton and 300-µm-thick beryllium target and are moderated via a polyethylene moderator. Samples, e.g., mortar samples with varying salt contents and part of an existing salt-damaged bridge, were irradiated by neutrons; then, the gamma rays following the neutron capture reaction were detected by germanium detectors placed near the samples. From the results, we obtained the detection sensitivity of the chloride content in a medium.