Compressive failure analysis of seawater-mixed aluminate cement concrete based on digital image correlation technique

For coastal and marine construction projects where fresh water is not readily available, the direct use of seawater in concrete production is an alternative option. In this paper, the digital image correlation (DIC) technique was utilized to observe the full-field deformation of seawater-mixed aluminate cement concrete under the curing conditions of freshwater/seawater (CAF/CAS) in the whole process of compression. The displacement and strain fields of the concrete cubes were mathematically obtained by way of correlation registration algorithms and strain window method to clarify the compressive deformation and failure mechanism of seawater-mixed aluminate cement concrete. The test results revealed that the deformation process could be divided into four stages, including the compaction stage, the elastic deformation stage, the crack propagation stage, and the failure stage. Furthermore, the crack propagation in the concrete was quantitatively evaluated by the local strain analysis, which demonstrated that the failure of both CAF and CAS resulted from the combination of shear failure and tensile failure perpendicular to the loading direction. However, cracks in CAF were dispersed and discontinuous whereas those in CAS was concentrated perforation and showed obvious brittle failure characteristics. Subsequently, the statistical analysis of displacement and strain in the concrete revealed the improved internal bond strength and compressive strength in CAS in comparison with CAF. [Display omitted] •DIC was employed to measure the compressive deformation of aluminate cement concrete.•Deformation stages of seawater-mixed aluminate cement concrete were identified.•Local crack propagation and failure mechanisms under different curing conditions were quantitatively probed.•Contrasting compressive deformations: CAF exhibited dispersed, and CAS showed concentrated and perforated failure.