The Research Of Waste Glass Mortars On Resistance To Sulfate

The durability of concrete has commonly been studied by people as a focus of concern. Sulfate erosion is important aspect of concrete damage degradation. Meanwhile, its experimental study had not great breakthrough. A lot of work is still in the basic state, even the serious lag. The durability of concrete has commonly been studied by people as a focus of concern. Sulfate erosion is a important aspect of concrete damage degradation. Meanwhile, its experimental study had not great breakthrough. A lot of work is still in the basic state, even the serious lag. Since the last century, Researchers had achieved some results in which fly ash, slag and silicon ash as admixture in concrete. Compared with the powder materials, glass powder is also slowly rising. But most of the tests about glass powder remain in the initial stage, such as glass instead of stones and sand, but the durability of it is few involving.In this article, we grinded glass to powder, and divided into three particle size range. Then we take different size glass powder to replace part of cement mixed into cement mortar. After standard curing, these cement mortars were put in tap water and 5% sodium sulfate solution for 6 months. Soak specimens will be tested compressive strength once a month flexural, and analysis the change rule of macroscopic properties strength, deformation, apparent morphology and mass loss. Intensity change rate as the parameter reflects the ability of the cement mortar on corrosion resistant. By means of SEM and XRD testing, obtained the different erosion depth of the cement mortar specimens after corroded by sulfuric acid, and its internal damage and corrosion product generation. It reveals the microstructure evolution regularity of damage and degradation mechanism by sulfate erosion and study different aspects of cement mortar macros by sulfate erosion regularity and mechanism of degradation for more in-depth and comprehensive from macroscopic to microscopic.The results show that the gypsum and ettringite crystal generating in internal cement mortar are the main causes of its degradation in sulfate environment. Waste glass is similar to that of ordinary Portland cement in the form of concrete damage under sulfate erosion. So the appropriate content and particle size of glass powder is helpful to improve mechanical properties and durability of the mortar specimen. Waste glass powder can partly replace cement as admixture, the strength of which decreases with substitution rate and the increase of particle size. Experiments prove that it is advisable to replace at less than 20% and glass powder particle size is less than 75 microns; Comparing with fly ash, glass powder is not easy to mix adequately as the result of the structure form for cement. Generally, when glass powder is grinded less than 75 micron, these mechanics performance can be similar with fly ash, even the late strength is more likely than fly ash.