ISSN 2319-5347, ISI Impact Factor: 0.763

VOLUME 03 NO. 02 APRIL 2014:

Title:       Improved neutron-based system for NDE of salt contamination and moisture in historic masonry
Authors:   Amde M. Amde, Richard A. Livingston
Abstract: Cycles of soluble salt deliquescence and dehydration in historic brick masonry in response to cycles of fluctuating moisture levels are known to have damaging effects over time. Non-destructive determination of the depth and degree of salt contamination and determination of moisture content in historic masonry are among some of the measurements that are needed to design appropriate remedial action. The focus of the paper is on an improved portable non-destructive evaluation system based on prompt gamma neutron activation (PGNA). The system works by irradiating a section of a structure with neutrons from a portable neutron generator. The gamma rays of characteristic energies resulting from interaction with target elements such as hydrogen, chlorine, sulphur, sodium and potassium are detected. The results can be used to map the spatial distribution of soluble salts in the structure. Several case studies and applications of the improved non-destructive evaluation system are discussed. It is concluded that the improved portable non-destructive evaluation system is a useful tool for quantitative analysis of elements associated with moisture, salt and other materials in historic masonry structures.

Keywords: Non-Destructive Evaluation, Historic Masonry, Brick Masonry, Gamma Rays, Salt Contamination, Neutron Activation
Page No:     188-193

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