This study investigated the improvement in a type of sand using a geopolymer made of recycled glass powder (RGP) as the base material and sodium hydroxide (NaOH) as the alkaline activator. Using maximum uniaxial compressive strength (UCS), the impact of alkaline activator concentration and the RGP content were investigated to determine the optimum mix design. Groundwater level increments were simulated through a laboratory procedure to study the effect of curing age and capillary action on the behavior of stabilized soil. The UCS of samples at different ages (14, 28, 45, and 60 days) and different degrees of saturation (Sr=0%, 20%, 50%, 80%, and 100%) were determined and their stress-strain diagrams were drawn. Using the stress-strain relationships, UCS, modulus of elasticity (Es), shear modulus (G), and resilient modulus (Mr) of the stabilized soil were estimated. The results showed that fully saturated stabilized samples did not disintegrate and exhibited a considerable UCS of up to 1.88 MPa at the age of 60 days. The greatest observed reduction in the UCS through saturation was between Sr=0 to 20%. To further investigate and validate the mechanical results, chemical and microstructural studies including X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX), X-ray diffraction analysis (XRD), and Fourier transform infrared spectroscopy (FTIR) were carried out. The results showed that during the curing period, the silicon/aluminum (Si/Al) ratio increased from 2.98 in untreated soil to 4 in stabilized samples, indicating active geopolymerization, which enhanced UCS and reduced the potential for disintegration. Additionally, the crystal size decreased from 53 to 24 nm for the 45-day stabilized samples when the degree of saturation changed from 0% to 100%. This finding suggests that if RGP-based geopolymer-stabilized soil contacts water after fully drying, geopolymerization reactions will resume that involve the dissolution of both crystalline and amorphous phases.

Molybdenum ore tailings, iron ore tailings and waste glass powders are important industrial solid wastes, mainly composed of silicate minerals and quartz, which are expected to become alternative resources for inorganic nonmetal industrial materials. In this paper, the ultra-lightweight ceramsite was prepared by the synergistic sintering of molybdenum ore tailings, iron ore tailings and waste glass powders according to their characteristics of silicate minerals. The physical and mechanical properties were investigated when the sintering temperature was between 1100 and 1140 degrees C. The evolution of mineral phases and formation mechanism of pore structure during sintering were studied by XRD, FT-IR, SEM, TG-DSC and HSM. The results showed that in the sintering process, the waste glass powders and the pargasite in iron ore tailings first melted to produce the initial liquid phases. Then the anorthoclase and the quartz in molybdenum ore tailings melted to produce a large amount of liquid phases. These liquid phases covered the gas generated by the oxidation of SiC, thus forming a rich pore structure. At the same time, the [Si2O64-] and Ca2+, Mg2+ in the liquid phases derived from quartz and pargasite melting recrystallized to form diopside, which was conducive to the improvement of mechanical properties of ceramsite. When the raw material ratio of molybdenum ore tailings, iron ore tailings and waste glass powders was 6:2:2 and the sintering temperature was 1120 degrees C, the pore structure of the ceramsite as prepared was uniform and rich and mostly closed. The density was low and the mechanical propertities were excellent. It has a good application prospect in the field of building thermal insulation and sound insulation.

The massive accumulation of waste seashells, waste sludge and waste glass not only occupies a large amount of land resources, leading to a shortage of land resources, but also causes serious soil-water-air composite pollution over a long period of time with the role of the surrounding environment, which poses a serious hazard to the ecological environment and public health. In this study, the effect patterns of waste glass powder (WGP) on the workability, mechanical properties, microstructure and carbon emission of seashell powder calcined sludge cement (SCSC) slurries prepared using waste sludge and waste seashells as supplementary cementitious materials in place of part of the cement clinker were investigated. The hydration process and microstructure of the materials were characterized by heat of hydration tests, thermogravimetry (TG-DTG), infrared Fourier transform (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the addition of WGP improved the fluidity of SCSC slurries and reduced the shear stress of SCSC slurries without changing the flow pattern of SCSC slurries, and all the slurries conformed to the power law model. The compressive strength of SCSC slurries increased by 25.26 % with 5 % WGP addition. The CO2 emissions per cubic meter of SCSC slurries were reduced by 4.43 %, 8.81 %, 13.5 % and 18.23 % for WGP additions of 5 %, 10 %, 15 % and 20 %, respectively. These results can provide a new way for the efficient resource utilization of waste seashells, waste sludge and waste glass, and reduce the CO2 emission during the cement production process, promoting the clean production of cement.

This study focuses on investigating the thermal, physical, and mechanical attributes of a light-weight fired earth brick composed of clay and dune sand, stabilized with lime. The study explores the impact of incorporating alfa plant powder and glass powder, constituting 15% and 10% respectively, relative to the soil matrix weight. This addition aims to attain optimized thermal, physical, and mechanical characteristics. Employing the statistical software, Statgraphics, experimental designs were created and analyzed, allowing for optimizations. The outcomes demonstrated a notable reduction in thermal conductivity, up to 42.36% and 23.91%, with the inclusion of alfa plant powder and lime, respectively. However, this led to a decrement in physical and mechanical properties. Conversely, the introduction of glass powder led to a decrease of total water absorption rates by as much as 4.52%. Utilizing the statistical program, an optimal ratio of 10.26% alfa powder was suggested, resulting in a brick with a thermal conductivity of 0.384 W/ m.K, a compressive strength of 8.561 MPa, and a total water absorption rate of 26.922%. These findings underscore the potential of incorporating alfa plant powder to enhance fired earth bricks, particularly in terms of thermal insulation. Additionally, it presents a sustainable and eco-friendly material technology.