Currently, most cities landfill most waste glass, resulting in the waste of resources and environmental pollution. Therefore, to realize the recycling of waste glass, solid waste glass was recycled and broken. Waste glass sand was prepared according to the gradation of natural river sand particles and the fineness modulus screening. It was used as an alternative material to natural river sand and mixed with mortar materials with different replacements. Analysis of the mortar with different replacements (0%, 20%, 40%, 60%, 80%) was conducted by combining macro and micro tests on the change law and influence mechanism of permeability, mechanical properties, and microstructure. The results showed that: the replacement of waste glass sand effectively improved the gas permeation resistance of mortar; with the increase of replacement, the gas permeation resistance of mortar roughly showed a trend of increasing first and then decreasing. The replacement of waste glass sand at 20% can better promote cement’s hydration so that the mortar’s porosity is reduced by 16.5%. The gas permeability decreases by 57.4%; the compressive strength increases by 3%, and the elastic modulus increases by 5.9%. When the replacement rate of glass sand is 20%, the test performance of mortar is the best among the five groups.
This experimental study investigated the effect of heating rate on mortar gas permeability and microstructure. The mortar was heated to three target temperatures (400 °C, 500 °C, and 600 °C) at three heating rates (5 °C/min,10 °C/min, and 15 °C/min). The variations of gas permeability and porosity were measured simultaneously at different confining pressures, and the changes in mortar microstructure were analyzed by NMR and SEM techniques. The results show that the porosity and gas permeability increase with an increase in temperature and heating rate. The gas permeability and porosity continue to decrease as confinement is increased due to a reduction in the pore volume. The microstructure observed by SEM indicates that the high heating rate induces some microcracks at 500 °C and 600 °C. The fractal dimension based on NMR can quantitatively characterize the complexity of the mortar pore structure and shows a quadratic decreasing relationship with gas permeability and porosity.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.