Modeling and experimental implementation of infrared thermography on concrete masonry structures

• Numerical and experimental study on heat transfer in partially grouted concrete masonry walls.
• Steady state and transient heat transfer modeled using FEM and finite difference method.
• Numerical results validated through full scale experiments on concrete masonry walls.
• Outlier analysis implemented to allow an enhanced infrared image of internal voided regions.

This paper is a combined numerical and experimental study which aims to demonstrate the implementation of the infrared thermography (IRT) method for the non-destructive evaluation of concrete masonry structural components. Specifically, a three-dimensional finite element (FE) analysis is formulated and implemented to predict both steady state and transient heat transfer in masonry specimens. A micro-element approach is followed to build the FE model geometry of the masonry walls. The model provides surface temperature contours which are the prime interest of infrared thermography. Three different scaled masonry specimens with identical thermal properties are considered for this study. The FE simulation results of heat diffusion are initially compared with finite difference method predictions for one specimen. Subsequently, the FE results are validated by implementing experimentally the IRT method on the other two specimens. The numerically predicted temperature values agree well with the actual measured values which validate the use of the IRT method for the nondestructive evaluation of concrete masonry components.