Papers by Keyword: Steel Slag

Abstract: Reusing industrial waste is a sustainable and eco-friendly way of minimizing environmental pollution in society. In addition, the stabilization of soils with non-conventional stabilizers has been shown to ameliorate engineering features of soils and reduce the cost of construction of road works. This study investigated the impacts of steel slag (SS) on the properties of poor lateritic soil (LS) for road pavement applications. Varying percentages of steel slag from 0-30% of soil dry weight in 5% intervals were employed to stabilize the soil. Plasticity index (PI), Maximum dry density (MDD), Optimum moisture content (OMC), California Bearing Ratio (CBR), Uniaxial Compressive strength (UCS), and chemical composition including the microstructural analysis of the untreated and treated soil were evaluated. With increasing slag content, the PI value decreased significantly from 22.47% to 9.20% indicating a nearly 60% reduction in PI at 20% SS treatment. The soil density became higher with a corresponding decrease in OMC as the SS content increased. The MDD increased from 1.56 g/cm³ for natural soil to 2.10 g/ cm³ at 25% SS content, and further addition of the material reduced the soil density. The CBR and UCS results show a general increase in values with higher SS content. The soaked CBR increased from 11.55 – 22.32% as SS content increased from 0-30%. The 28th day UCS reached the optimum value of nearly 380 kN/m² at 25% SS compared to 93.57 kN/m² of the natural soil. The iron oxide, which is a cementing agent, increased as the content of SS became higher in the soil. The microstructural analysis using scanning electron microscopic (SEM) results showed the formation of larger particles and a reduction in pore spaces as the SS content increased. The 25% SS treated soil satisfies the required 12% PI and minimum soaked CBR of 20% for foundation application as a subbase material in light traffic roads. These results suggest that adding 25% steel slag makes the lateritic soil a suitable material for both subgrade and sub-base pavement layers.

Abstract: Roads play an important role in realizing the development and distribution of development results in certain areas. Pavement performance shows a decreased durability over time-related to how long the pavement construction can carry out its functions without experiencing fatal damage. This study aims to identify the effect of using steel slag as a substitute for filler with steel slag content of 0%, 1%, 2%, and 3% on concrete compressive and flexural strength values. This study used an experimental method by conducting experiments for testing the compressive and flexural strength of concrete specimens. The results showed that the use of steel slag as a substitute for filler obtained the average compressive strength value of MPa, 21.87 MPa, 22.17 MPa, and 28.47 MPa in concrete aged 28 days with steel slag content of 0%, 1%, 2% and 3% 25.07 respectively. The average flexural strength of concrete aged 28 days with steel slag content of 0%, 1%, 2% and 3% were 3.84 MPa, 2.83 MPa, 3.41 MPa, and 4.09 MPa respectively. The composition of 3% steel slag was the optimal composition as a filler replacement material. The pozzolanic properties of steel slag could increase the durability and density of the concrete specimen, but it required a long curing time and the increase in the initial strength of concrete slows down.

Abstract: Limited land with good soil quality results in infrastructure being built in areas with unfavorable soil characteristics. development. Soil with unfavorable characteristics one of which is swamp land. Swamp soil needs to be stabilized if we want to build buildings on that land, the stabilizing material used can be silica waste or other binding materials. In this test, steel slag, fly ash, and glass bottle powder were used as the main stabilizers, with a fixed percentage of 20% steel slag and 20% fly ash, and glass bottle powder as an independent variable with a percentage of 0%. 5%, 10%, and 15%, and with the aging time of 0, 3, and 7 days. Testing the characteristics of Situ Rawa Arum, Jl. Kp. Tegal Wangi No. 62, Kec. Gerogol City of Cilegon Banten has poor soil carrying capacity with a CBR value of 1%. After stabilization using steel slag, fly ash, and glass bottle powder there was a significant change. The most optimum change in soil carrying capacity occurred in a mixture of 5% glass bottle powder + 20% steel slag + 20% fly ash with a CBR value of 31%.

Abstract: A surface layer of permeable bituminous mixture has been laid on an existing pavement section. This layer, in addition to providing the pavement with draining characteristics and acoustic comfort, incorporates a residue that is difficult to apply, the ladle furnace steel slag. The tests carried out show that the designed mixture meets the requirements in terms of mechanical properties, resistance to the action of water, and porosity. Furthermore, in-situ tests on the completed layer demonstrate its excellent permeability, as well as a surface texture suitable for use on roads and highways. The introduction of the ladle furnace slag makes it possible to design a high-performance, but also environmentally sustainable, mix.

Abstract: Building gypsum has the disadvantage of short setting time and fast hardening characteristics. Based on the systematic experiments, a combined retarding system of phosphoric acid modified steel slag (3%, gypsum-based) and protein-based material (Sika 200P 0.005%, gypsum-based) is proposed. The initial setting time of gypsum is prolonged to 206 min and the final setting time is 221 min. The retarding effect for desulfurization building gypsum is significantly better than Sika 200P, and the cost is greatly reduced.

Abstract: The impact of admixture of both Ordinary Portland Cement (OPC) and steel slag was examined on the geotechnical properties of the lateritic soil, by conducting basic geotechnical tests: Particle size analysis, Consistency limits, Compaction, California Bearing Ratio (CBR) and Unconfined Compressive Strength (UCS) on both the natural and stabilized soil samples and results were subjected to statistical analysis using 2-way ANOVA (Analysis of Variance) at 5% level of significance. The natural soil was classified as s A-7-6 and MH under standard soil classification systems. Addition of steel slag lowered the liquid limit (LL) and plasticity index (PI), while cement increased the LL and decreased PI of the lateritic soil, respectively. With increasing content of slag and cement, maximum dry density increased with the corresponding decrease in optimum moisture content. CBR and UCS of the stabilized soil increased substantially with increasing contents of slag and cement. Both steel slag and cement have statistically significant effects on the geotechnical properties of the lateritic soil. Hence, this soil can be stabilized with addition of 12% steel slag and 6% cement contents for its application as an improved subgrade material for light trafficked pavement. Keywords: Lateritic soil, steel slag, cement, stabilization, Index properties, strength indices.

Abstract: Steel is produced from iron ore and purification of metal scrap, leading to manufacture of hundreds of tonnes of steel slag each year. This study investigated the optimum replacement of granite with Ife Iron and Steel Nigeria Limited (ISN) slag that produce maximum Compressive Strength (CS), Split Tensile Strength (STS) and Flexural Strength (FS) of concrete using Response Surface Methodology (RSM) from Design Expert Version 7.0. The outcome of the study showed that the optimum replacement of granite with ISN was 28.85% ISN at 0.47 W/C.

Abstract: Effects of Water cement ratios on strengths characteristics of concrete produced with Recycled Iron and Steel Slag (RISS) aggregates was studied to understand the structural integrity of RISS aggregate in concrete and to determine the veracity of RISS aggregate as alternative aggregate to granite in concrete works. Mineralogical composition of the aggregate showed Silicon oxide (quartz) as the common mineral; both aggregates are well graded, strong and durable. Lower water cement ratios improved both the compressive and flexural strengths of RISS and granite concrete.

Abstract: Steel slag (SS) is a kind of industrial solid waste usually been dumped at landfills and causes environmental pollution. Previous studies have demostrated that SS can be an alternative material to be used for making concrete and could achieve good mechanical properties, which not only reduce natural resources depletion but also improve environmental quality. This study aims to evaluate the effectiveness of SS as supplementary cementitious material (SCM) partially replacing cement on workability and mechanical properties of fresh and hardened concrete. X-ray flouresence test, slump test, compressive strength test and ultra pulse velocity test have been conducted. Mix designs are determined with replacement proportion of cement by SS of 0, 10%, 20%, 30%, 40% and 50%. Results show that replacement of cement by SS up to 50% increase the workability of concrete. The density of concrete ranges from 2083 to 2373 kg/m³, with and without replacement of SS at curing age of 1-day, 3-day and 28-day. Compressive strength of concretes incorporating SS is lower than that of plain concrete. 1-day and 3-day compressive strength of concrete incorporating SS decrease with the increase in replacement of SS while 28-day compressive strength reach peak at 30% replacement and further replacement of SS reduce 28-day compressive strength. The UPV value of concrete have good relationship with compressive strengh with the correlation coefficient of 0.92, 0.87 and 0.70 of 1-day, 3-day and 28-day experiment data, respectively. This study indicates the SS can be used for making concrete.

Abstract: The search for sustainable materials has been increasingly growing due to the world environmental impacts faced. With the improper disposal of PET packaging and the waste generated by steel making, such as slag, a composite of these materials was created in search of a sustainable product. The composite has as its matrix the polymer and its particles are geopolymeric of the steel slag. The polymer composites were manufactured with concentrations of 0%, 20%, 40% and 60% of geopolymer. The characterizations showed that they are composites with low moisture absorption and that the affinity between the matrix and the reinforcement is impaired as the amount of charge increases. It was possible to realize that composites are good materials for future studies for possible future applications, such as ballistic vests. Composites are great precursors for achieving product sustainability due to the feasibility of reusing waste and disposing of it improperly in the environment.