Study on performance and fractal characteristics of high-strength manufactured sand concrete with different MB values

The mud powder in the manufactured sand will have an influence on indicators of concrete (MSC), and methylene blue value can quantitatively indicate content. To demonstrate impact MB values performance microstructural characteristics concrete, paper designed five high-strength MSC proportions at by controlling clay On this basis, workability, chloride migration coefficient, relative dynamic modulus elasticity ( P ), mass loss rate η dry shrinkage were tested under mix ratios, relationship between microstructure, fractal characteristics, compressive strength f cc ) was analyzed combining SEM technology theory. experiment showed that: higher MB, lower fluidity MSC, cohesiveness gradually increases, while water retention remains basically unchanged. In addition, coefficient after 300 freeze-thaw cycles first increases then decreases, drying decreases corresponding to turning point these three changes are all 1.10. With 0.85 1.10, degree hydration is overall structural compactness better. value, more inadequate mineral components such as fly ash that not been hydrated inside increase, which leads gradual decrease structure compactness. when small, image texture relatively simple, dimension large. When large, complex, small.