Mechanical Properties of Concrete Modified with Silica Fume and Integral Waterproof and Comparison with Waste Glass Aggregate Concrete

This study includes the effect of using different dosages of integral waterproof Admixture and silica fume on some mechanical properties of concrete. Concrete improved by using different ratios of integral water proof admixture(IWP admixture) to increase strength and durability, this admixture used as percentages from cement weight in each mix ranged from 0.0% to 2% ( 0.0, 1.0%, 1.2%,1.4%,1.6%,1.8%, and 2%), compressive strength test done for cubes with (10*10*10) cm for each mix. The flexural strength test was done by (10*10*40) cm beams and tested after 28 days of curing. comparison study was made between silica fume mixes properties and mixes without silica fume. Adding IWP admixture leads to increase mechanical properties of ordinary concrete, the reference mix shows compressive strength equal to 26.38 MPa, while mixes with 2% IWP gives 38.8 MPa in this study. The study also includes the effect of using 2 main dosages of silica fume to the mixes that contain IWP, the new concrete with two admixtures show better values of compressive, tensile and flexural strength comparing with mixes with only IWP, the compressive strength increased from 38.8 MPa for ordinary IWP mixes to 52.3 MPa for 10% silica fume concrete mixes, and also the flexural strength increased from 4.8 MPa for mixes with only IWP to 7.3 MPa for mixes modified with 10 % silica fume. Study include also using waste glass as fine aggregate in mixes contain IWP and 10% silica fume and that show more increment in mechanical properties also.

Unconventionally Made-Cellular Glass Aggregate

Improving the original manufacturing process in microwave field of a cellular glass aggregate using a recipe containing colored consumed drinking bottle, calcium carbonate (CaCO3) as an expanding agent, sodium borate (borax) as a fluxing agent and sodium silicate (Na2SiO3) as a binder is shown in the work. The main adopted technological measures were the advanced mechanical processing of residual glass at a grain dimension below 100 μm and especially the use of a high electromagnetic wave susceptible ceramic tube with a wall thickness reduced from 3.5 to 2.5 mm for the protection of the pressed glass-based mixture against the aggressive effect of microwave field and, in the same time, to achieve a preponderantly direct heating with electromagnetic waves. Of the tested variants, a recipe with 1.6 % calcium carbonate, 6 % borax, 8 % sodium silicate and the rest residual glass was determined to be optimal. The cellular glass aggregate had the bulk density of 0.22 g/cm3, heat conductivity of 0.079 W/m·K and compression strength of 5.9 MPa. The specific consumption of energy was very low (0.71 kWh/kg) below the range of reported values of the industrial processes consumption (between 0.74-1.15 kWh/kg).

Effect of Glass Cullet Size and Hydrated Lime—Nanoclay Additives on the Mechanical Properties of Glassphalt Concrete

In this study, the use of glass waste as aggregate in asphalt mixtures was investigated. Maximum glass aggregate size options of 0.075, 2.00, 4.75 and 9.5 mm. were selected. Conventional bitumen, nanoclay-modified bitumen and hydrated lime-modified bitumen were used. Dense graded asphalt mixtures were designed according to the Marshall method. Mixtures were evaluated for low-temperature cracking, resistance to water damage, fatigue, and permanent deformation behavior with repeated creep, indirect tensile strength, indirect tensile fatigue, modified Lottman and Hamburg wheel tracking tests. Increasing glass aggregate size reduced the water damage resistance of asphalt mixtures because of the smooth surface of the glass particles and nanoclay and hydrated lime modification improved the mechanical properties of the asphalt mixtures. Using 2.00 mm sized maximum glass aggregate showed relatively less water damage and deformation properties due to higher internal friction which is due to the greater angularity of the glass particles. In addition, there was a significant correlation between repeated creep test, modified Lottman methods and Hamburg Wheel tracking test from the viewpoint of deformation and water damage assessments.

The Process Development of Glass Cullet and Recycled Glass Aggregate for Improving Recycling Rate

Due to depletion of resources and the spread of environmental pollution, the sustainability of raw materials is emerging as an important issue. Glass bottles are one of the products that are easy to recycle, and many studies have been conducted to improve the recycling rate. In this study, we attempted to develop the waste glass bottles process that can be recycled into a glass cullet and recycled glass aggregate. To produce a cullet from waste glass bottles(WGBs), color quality standards must be satisfied. Therefore, we applied a multistage color sorter to the experiment. The recycled aggregate glass must adjust the particle size. Thus, we experimented with the optimum crusher selection test when applying the crushing process. And, we confirmed the appropriateness of process by aspect ratio analysis of product. In addition, we confirmed the trends in the data required to set the optimum design and operating conditions of the selected vertical shaft impact(VSI) crusher using discrete element method(DEM) simulations.

Bond and flexural performance of basalt fiber–reinforced polymer bar–reinforced seawater sea sand glass aggregate concrete beams

This article proposes a new type of basalt fiber–reinforced polymer (BFRP) bar–reinforced seawater sea sand glass aggregate concrete (SSGC) beam with broad application prospects in ocean engineering. Crushed tempered glasses were utilized as coarse aggregates in the concrete mixture to realize the efficient and harmless recycling of waste glass. First, the bond behaviors between the BFRP bars and SSGC with different glass aggregate replacement ratios were investigated. Then, four-point bending tests were conducted to investigate the flexural performance of the SSGC beams completely reinforced with BFRP bars. Based on this, the tested flexural strengths were compared with the calculated strengths to evaluate whether the existing specifications were still applicable to the design of the BFRP bar–reinforced SSGC beams. Test results showed that although the compressive strength of the SSGC gradually decreased with increased glass aggregate content, the bond performance between BFRP bars and SSGC did not follow the same degradation pattern. There were no obvious differences in the form of the bond–slip curves between BFRP bars and different types of SSGC. With increasing glass aggregate content, the ultimate bearing capacity and energy consumption of BFRP bar–reinforced SSGC beams decreased. All calculated ultimate flexural capacities were higher than the experimental values, which shows that the application of existing specifications to BFRP bar–reinforced SSGC beams needs to be studied further.