Concrete cracking risk analysis at early age by means of a ring test

Early-age cracking in massive concrete structures is a critical issue affecting durability and maintenance costs. This study introduces the BT-Ring test, an adaptation of the Schlitter ring test, designed to evaluate stress evolution due to restrained thermal and autogenous deformations. The test replicates in-situ conditions, enabling a comprehensive assessment of cracking risk by means of a complete analytic solution for the stresses generated during the test. Experimental results reveal an initial compressive stress phase followed by tensile stress build-up, with cracking occurring when the mean orthoradial stress exceeds the concrete’s tensile strength. A delay between predicted and observed cracking highlights variability in tensile strength and possible size effects. Numerical modelling aligns well with experimental data, confirming the test’s reliability in stress prediction when all the parameters of the model are correctly characterized. Future research should focus on refining numerical models by incorporating damage-based approaches to account for heterogeneities and size effects. Additionally, applying this methodology to various concrete formulations, including low-carbon mixtures, would enhance its applicability. The BT-Ring test, combined with advanced modelling, presents a promising approach for optimizing concrete formulations and mitigating early-age cracking risks in large-scale structures.