Investigating the correlation between mechanical and durability properties of non-aerated concrete with macro pores determined by digital image analysis

The durability of concrete structures is a major concern, and one of the most important parameters affecting durability is porosity. The porosity of concrete is directly related to several properties of concrete, including water absorption, permeability, penetration of corroding substances, and strength. Measuring the porosity of concrete as a percentage of the total volume can help assess its durability. A novel process is developed in this study to estimate the macro-porosity percentage using image processing that can be applied to non-aerated concrete with various coarse aggregates. The accuracy of the porosity estimation has been validated by comparing the water absorption test data through statistical validation techniques. In addition to the porosity estimation, several durability tests have been conducted, including water sorptivity, rapid chloride ion penetration, ultrasonic pulse velocity, sulfate attack, and compressive strength tests. The results of these tests are correlated with the porosity percentage estimated from digital image processing, and the relationship between porosity and durability parameters is developed. Rapid chloride ion penetration, ultrasonic pulse velocity, and compressive strength exhibit a coefficient of determination of 91.52%, 82.62%, and 96.98% with porosity, respectively, which indicates the effectiveness of the proposed technique.