A new image analysis procedure for quantifying microcracks from three-dimensional (3D) X-ray microCT images of concrete is presented. The method separates air voids and aggregates by combining filtering morphological operations. It was applied to study the effects supplementary cementitious materials (SCMs) curing age on autogenous shrinkage-induced in low w/b ratio concretes, determine represe...

The high autogenous shrinkage of alkali-activated materials made from slag and fly ash is recognised as a major drawback with regard to the use construction materials. In this study, metakaolin was introduced into slag-fly (AASF) paste mitigate shrinkage. mitigation mechanism explained by studying influences on microstructure, related properties, mechanical properties AASF paste. It found that ...

The effect of hydrogels containing nanosilica (NSi) on the autogenous shrinkage, mechanical strength, and electrical resistivity cement pastes was studied. interaction between surrounding cementitious matrix examined using thermogravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM). addition decreased shrinkage in this reduction showed a ...

This study aims to compare the developments of mechanical properties and autogenous shrinkage related alkali-activated materials-based concrete (AC) ordinary Portland cement-based (OC) against curing age degree reaction. Temperature Stress Testing Machines are utilized monitor evolution internal tensile stress cracking occurrence in restrained concrete. It is found that AC shows lower strength-...

It is well-known that supplementary cementitious materials (SCMs) and low water-to-binder (w/b) ratio increase autogenous shrinkage, but the impact on microcracking long-term transport properties less understood. This paper examines effect of induced by shrinkage concretes cured up to ~3.6 years. Variables include SCM type (9% SF, 70% GGBS), w/b (0.20–0.45), maximum-aggregate-size (MSA: 5–20 mm...