Title: Macroscopic Evaluation of Water Penetration Resistance in Concrete with Neutron Imaging
Author(s): Yuichi Yoshimura, Maki Mizuta, Hideyuki Sunaga, and Yoshie Otake
Publication: Symposium Paper
Appears on pages(s): 495-507
Keywords: neutron, compact neutron source, neutron transmission imaging, water content, water penetration, water penetration rate coefficient
The development of a method to evaluate water penetration in concrete is beneficial for analyzing the durability of concrete structures since water in concrete affects the progress of degradations such as salt attack, carbonation, alkali silica reaction. However, water in concrete is generally detected by an embedded electric moisture sensor, it is difficult to obtain continuous spatial distribution about water diffusion. Water penetrated into concrete with a thickness of 5 cm was observed by neutron imaging using a room-size neutron source based on a compact accelerator and macroscopic analysis on water penetration was carried out. The results showed that the neutron transmittance corresponds to the water content and the moisture profile. Then transfer properties of
water in concrete were obtained nondestructively and quantitatively. In addition, the relationship between the test results evaluating void structure and the water penetration resistance was considered. This report shows a new simple method to evaluate water penetration in concrete.