Using X-ray transmission/attenuation to quantify fluid absorption in cracked concrete

Abstract

Abstract:Cracks can alter the rate of fluid transport in concrete. Unfortunately, however, quantitative information is lacking to provide definitive statements regarding the extent to which cracks reduce durability or long-term performance. This paper describes a study that used X-ray transmission/attenuation to determine the influence of cracking on the absorption of fluid in concrete. Specifically, an experimental method is presented which uses a wedge splitting test to pre-crack specimens. These pre-cracked specimens were dried and ponded with water. At various times after the start of water ponding, X-ray attenuation measurements were taken using a grid of points around the crack. By repeating this measurement and comparing the change in X-ray transmission/attenuation, the ingress of the fluid could be determined by locating the position of the moisture front. An approach is presented to determine the geometry of the crack by using water absorption perimeter measurements of the wetting front in the concrete.

Dynamic effect of water penetration on steel corrosion in carbonated mortar: A neutron imaging, electrochemical, and modeling study

“…Traditional techniques for measuring moisture distribution, such as embedded relative humidity sensors [11,12] and gamma-ray attenuation [13], cannot be used for the SCI. Modern techniques, including micro-X-ray computed tomography (μXRCT) [14][15][16][17] and neutron radiography [18,19], are able to achieve a resolution in micro meter range, which have been commonly used to monitor the rapid water absorption in cement-based materials. As X-rays are not sensitive to water, contaminated water with highly sensitive ions was used (e.g., Cs [17,20]) or techniques that can enhance the measured signal (e.g., X-ray dark-field imaging [15]) are needed.…”

Neutron Radiography Based Visualization and Profiling of Water Uptake in (Un)cracked and Autonomously Healed Cementitious Materials

“…Capillary water absorption in sound and cracked mortar and concrete has already been investigated in several studies by X-ray [ 9 , 27 , 28 , 29 ] or neutron radiography [ 17 , 30 , 31 , 32 , 33 , 34 , 35 , 36 ] experiments. In the research of Van Tittelboom et al [ 30 ], the self-healing efficiency of mortar with encapsulated healing agents was visualized for the first time by neutron radiography.…”