To understand the fundamental mechanisms behind the formation of plastic shrinkage cracking in concrete, the development of suctions must be considered. By investigating this phenomenon, the study endeavoured to adapt existing instrumentation to effectively measure in-situ suctions in concrete. Suction profiles were generated from the implementation of the newly modified devices. It was proposed that the development of suctions in concrete was analogous to the suctions in fly ash. Thus suction profiles were developed in fly ash as a bridging step between the theoretical suctions in soils and the suctions in concrete.
By reviewing literature on the devices available for measuring suctions in geotechnical and agricultural situations, it was determined that tensiometers and hygrometers were the two devices most suited to this study. The paper discusses specific details to how the experiments were conducted, and refined, to determine the effectiveness of the devices to measure suctions. To validate findings, a comprehensive discussion on the compliance of the experimental data to the theoretical data was presented. This included the fitting of the Fredlund and Xing (1994) moisture characteristic curve and the comparison between the experimental and theoretical dimensionless data.