Investigation of the Strength Properties of Concrete Using Marble Powder and Iron Ore

. Concrete is a major concern for engineers because of its extensive use in the building sector. The production of concrete also uses a lot of materials all around the world. However, the price of energy, the expansion of manufacturing capacity, and environmental concerns are three of the most crucial factors to consider in the concrete industry, considering the fast urbanisation and modern market. Because of issues with pollution and the high price and low availability of sand and cement, the current research focuses on employing marble powder as a cement substitute and iron ore as a sand substitute. The commercial by-products of producing and polishing granite powder, waste iron powder (WIP) and waste marble powder (WMP), are mainly wasted and pose a threat to human health. Substituted with marble powder (5% and 10%) for the cement and iron powder (30%, 40%, and 50%) for the fine aggregate. The results were based on the material's compressive strength, flexural strength, and workability. The highest compressive and flexural strengths were achieved when 10% of the cement was replaced with marble powder and 50% of the iron ore was replaced with sand. According to the results, the strength qualities of concrete might be enhanced by using less marble and more iron ore. From both a financial and ecological perspective, recycling these components and incorporating them into concrete as a partial replacement makes sense.


Introduction
The widespread use of concrete in the construction industry makes it a major concern for engineers.Concrete production also accounts for a significant amount of global material use.However, in view of rapid urbanisation and the contemporary market, three of the most important aspects to consider in the concrete industry are the price of energy, the growth of manufacturing capacity, and environmental concerns.The current study investigated using marble powder as a cement substitute and iron ore as a sand substitute to address pollution and the high cost and low availability of sand and cement, respectively.Waste iron powder (WIP) and waste marble powder (WMP) are commercial by-products of making and polishing granite powder that are primarily wasted and constitute a concern for human health.Iron powder (30%, 40%, and 50%) and marble powder (5% and 10%) were used as cement and fine aggregate, respectively.Compressive strength, flexural strength, and workability were the key factors in determining the outcome.When 10% of the cement was substituted ICSTCE 2023 https://doi.org/10.1051/e3sconf/202340503008 E3S Web of Conferences 405, 03008 (2023) with marble powder and 50% of the iron ore was substituted with sand, the resulting material had the highest compressive and flexural strengths.The findings suggest that replacing some of the marble in concrete with iron ore could improve its strength.Reusing these materials and putting them into concrete as a partial replacement makes sense from both a financial and environmental standpoint.

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Promoting the use of waste that can be applied to various materials and for a variety of purposes in the construction industry by factories, both inside and outside the Sultanate,

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Making building materials from construction factory waste at simple rates of addition to reduce waste and pollution and protect the environment.

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Reducing the cost and increasing the performance of concrete by using leftover marble powder.Additionally, the national economy will be supported by the development of new sectors, such as the diversification of building materials available on the Omani market through waste recycling and the investigation of new employment opportunities.

Literature Review
The global construction industry has challenges in areas such as manpower, productivity, environment, mass transportation, water management, raw materials, durability and design life of construction items, chemical resistance, and more (Kuckian and Dalvi (2020)).The production of marble generates a significant amount of waste, according to research by Hamed et al. published in 2014.As for the garbage, The waste produced during mining, processing, and polishing is harmful to the environment, the soil, the water, and human health.This is just one of the many problems facing the construction industry worldwide, which also faces difficulties with manpower, productivity, environment, mass transportation, water management, raw resources, durability and design life of construction items, chemical resistance, and other issues.However, there's room for reusing marble scraps, especially in concrete manufacturing.Some scientists and engineers have investigated ways to reduce waste in the lab in a sustainable and responsible manner because of the harmful effects this substance has on the environment.In recent years, researchers have tried substituting waste materials like marble dust and iron powder for some of the concrete in concrete buildings.The ratios used to blend the various materials in concrete are the key to generating concrete that is strong and durable.Less cement putty could lead to greater voids, which could weaken the building.Many studies, however, investigated the effects of using varying amounts of marble powder in place of cement.Iron powder, at varying concentrations, can also be substituted for sand in concrete.
Using marble powder as a partial replacement for cement and iron powder for sand, this study assesses and reviews previous research and tests to determine the impact on concrete's performance and mechanical qualities.
Noha's 2013 case study research suggests that mineral additives can have an impact on the functionality of both fresh and hardened concrete.The study's author analysed and produced Table 1 below, which details the powdered marble's chemical and physical properties.

Table 1. Physical and Chemical properties of marble powder
As studied by Soliman, N. M. (2013), the chemical composition of marble powder and cement was similar in most aspects, like lime, alumina, silica, and magnesia, as shown in Table 2.The compressive strength of the concrete was increased by 10%, 25%, or 8% after 28 days when marble powder was added at a concentration of 2.5%, 5%, or 7.5%.After 56 days of testing, the marble powder's compressive strength increased by 13%, 29%, and 10%.At 56 days, the compressive strength of the control mix was 354 kg/cm The behaviour and strength of R.C. concrete are affected by the use of marble powder in concrete mixtures.
The compressive strength of concrete tested after 28 days was shown to drop by about 20%, 21.35%, 21.66%, 23.75%, and 26.6% when the proportion of marble powder in the mixture was increased from 10% to 20%.
Table 5 displays the mix ratio used in experimental studies to determine whether marble powder is an appropriate cement replacement in high-strength concrete.The study's goal is to learn how replacing cement with marble powder modifies the mechanical and durability properties of HSC.Marble powder was utilised at a zero, five, ten, fifteen, and twenty percent replacement rate.
Compressive and flexural strengths of concrete were shown to be improved when cement was replaced with marble powder (5%, 10%, and 15%) (Raghunath P.N. et al., 2019).S2 was 1.90 times stronger in compression than S1.There were increases in compressive strength of 7.19 percent, 9.23 percent, and 5.89 percent between S2 and S4.Compressive strength was decreased when cement was substituted by 15%, possibly because there was less cementing material.2015) studied the effects of using leftover marble powder in place of some of the cement on the compressive, split, and tensile strengths of M 20, M 30, and M 40 concrete classes.Make sure you're using the right amount of marble powder in your concrete mix.The dust from marble blocks contributes to air pollution.Substituting marble powder for cement is one way to lessen environmental impact.Waste marble powder with a fineness of 13% and a specific gravity of 1.5 was sieved via an IS-90-micron sieve before being mixed into the concrete.Analysing the properties of powdered marble debris.Flexibility of newly placed concrete: After being mixed, concrete was tested using the slump and C.F. methods.The concrete batch used for the consistency test was combined with the others before test specimens were made.The workability of concrete is evaluated using a slump cone after it has been mixed.

Graph 5. Various slump values for M20, M30 & M40 grades of concrete
Mixes like M20, M30, and M40 concrete became more workable when 20% cement replaced waste marble powder.Workability increases with 10% waste marble powder.WMP particles operate better due to their spherical shape, smooth texture, and higher surface area of contact.After 7 and 28 days in fresh water, the specimens were dried and tested for strength.The above graph is based on data from Noori, K., et al. ( 2018), Mechanical Properties of Concrete Using Iron Waste as a Partial Replacement of Sand, and it shows how increasing the iron waste content leads to a steady rise in compressive strength.The purpose of this study was to examine the effect of iron waste content on the strength development of concrete after 7, 14, and 28 days of curing.The results show that a composition of 12% iron waste produces the strongest concrete; beyond this point, adding more iron waste degrades the concrete.Adding 12 percent iron waste to concrete immediately boosts its compressive strength by 15 percent compared to control concrete after only 28 days.

Graph 10. Flexural strength with different percentages of Iron waste
The graph demonstrates that the flexural tensile strength decreases with an increase of iron waste of more than 12%.Therefore, it may be argued that the strength of concrete can be increased by using a tiny amount of iron waste in place of sand.(2018) Noori, K., et al.
The rising global demand for steel and the subsequent extraction of valuable ore generates IOT, as explained in the 2018 article "Experimental study on strength properties of concrete replacing cement by marble dust and sand by iron ore tailings" by Kumar, N. et al.Since IOT is a byproduct of slurry extraction and has very fine material properties, it can be utilised in place of fine aggregate.The decorative usage of marble dust is widespread in the building industry.Over twenty percent to thirty percent of all waste generated from quarry to finish consists of fine particles.If dumped outside, it could contribute to air pollution, which would have negative effects on human health and soil fertility.Recent research has investigated using marble dust as a partial cement replacement due to its high quality.Partial substitution of fine aggregate (natural sand) at 10%, 20%, 30%, and 40% and normal Portland cement (OPC) at 5%, 10%, 15%, and 20% was used to examine the behaviour of iron ore tailings (IOT) and marble dust when being carried across fresh concrete.Adding more IoT devices has been demonstrated to decrease the system's usability.The superplasticizer admixture "CONPLAST-SP340" was used to maintain the material's workability.A combination of 10% IOT and 5% marble dust was found to be the best option based on the strength characteristics.

Design of concrete:
The mix design was carries as per BS 8110 and BS 8500.The necessary quantity of each material (coarse aggregate, cement, sand, and water) was prepared.The mixer machine initially received the dry materials and began mixing them.
Water was gradually incorporated during the mixing process.

Concrete Mix procedure with replacement of marble powder and iron ore
The coarse aggregate and fine aggregate (sand) were then added to the mixer machine, with the sand being partially replaced with iron powder (30%, 40%, or 50% depending on the mix).Cement was added to the mixture when marble powder was largely replaced (by 10% or 15%, respectively).The components were blended by gradually adding water.The same process was repeated multiple times, each time with a different proportion of marble to iron powder.Applying oil to the cube and prism moulds required a brush.The mixture was put in three stages, or layers, in the moulds, then tamped down 25 times between each stage.Excess material was scraped off the surface of the mould with a tamping rod.The compacting machine was used to compact the mixture in moulds, eliminating air pockets.The concrete prisms and cubes were permitted to dry in their moulds for 24 hours before being removed.After curing for seven and twenty-eight days, respectively, concrete prisms and cubes were placed in the water tank.

Slump test:
At implementation sites and mixing stations, this test is considered one of the best and simplest ways to guarantee product quality.For testing, the concrete was poured into a mould in the shape of an elliptical cone manufactured from thick metal (at least 1.5 mm).It can be entered from both above and below.It stands at 30 centimetres tall, with a 10-centimetrewide top opening and a 20-centimetre-wide bottom one.The tamping rod used was 60 centimetres long and 15 millimetres in diameter.The mould's interior was polished and coated with oil.Assuming that each layer was compressed 25 times with the compaction rod, the mould was filled in three layers, with each layer's height being about equivalent to onethird of the mould's height.The edge of the mould was lined up with the top of the mixture after it had been tamped down firmly.After the mould was filled vertically, it was lifted gradually and in a straight line.After the mould was lifted, the slump was calculated by comparing the mould's height to that of the concrete's centre.

Compressive and flexural strength test
The compressive and flexure test were carried out for 7 and 21 days as per the EN 12350 and EN 13791 on fresh and hardened concrete test procedure requirements.

Workability results (Slump test)
The horizontal flow of concrete is examined in this test with no obstacles in the way.Slump cones are used to evaluate the workability of freshly mixed concrete.In the accompanying table, we can see the results for every possible mixture of marble powder and iron powder in concrete, albeit with different replacement ratios.Slump test results for mixtures with 30% (M2), 40% (M3), and 50% (M6) iron powder substitution for sand were raised by 22.5% and 45%, respectively, when 10% of the cement was replaced with marble powder.As can be seen in the table below, which compares mixes M3 and M5, the slump values reduced by as much as 20% when using a 15% marble ratio with varying iron levels.As the iron powder ratio rises, the slump cone values tend to fall, suggesting a correlation between the two.Mixes with a 10% marble ratio are more workable than those with a 15% marble ratio, demonstrating that increasing the replacement ratio of marble and iron powder reduces the mix's workability.Mix M6, with its appropriate replacement of 50% iron and 10% marble, increases concrete workability in comparison to the control mix.

Graph12. Slump test results for different mixes
The results were consistent with those found in the article "Effect of Using Marble Powder in Concrete Mixes on the Behaviour and Strength of R.C. Slabs"; increasing the amount of marble powder to cement from 2.5% to 5% to 7.5% to 10% raised the slump values by 40%, 60%, 36.7%, and 13%.N. M. Soliman (2013) Overall, replacing 10% of the cement with marble powder enhanced the fresh concrete's workability.As the iron replacement ratio increased, the slump cone values also rose.

Graph 13. Values Compressive and Flexural strengths for all mixes
Therefore, the compressive strength values of all specimens with 10% marble as a partial replacement of cement increased, unequivocally demonstrating M2, M4, and M6.After curing for seven days, the cubes had values of 32.5 MPa, 32.7 MPa, and 35.1 MPa, respectively.After cubing, the values for 21-day-cured cubes were 35.83MPa, 34.90 MPa, and 41.291 MPa, respectively.The cubes containing 15% WMP were found to be weaker than the control cube containing 0% WMP.In addition, as shown in M6, the optimal replacement ratio to boost compressive strength is 10% marble with 50% iron.
When we compare the outcomes of the variant mixtures (M2, M3, M4, M5, M6, and M7) to the reference variant (M1), we see that the compressive strength diminishes as the proportion of substitution with marble increases.The research in "An Experimental Examination on Mechanical and Durability Properties of Cement Replacing with Marble Powder" (Suresh, S. et al., 2019) lends credence to this conclusion.Because reducing the amount of cement in a combination reduces its compressive strength, using marble is analogous to this practice.And after 7 days, we found that iron contributed more to the overall compressive strength improvement than marble did.This finding is in line with that found in "

Flexural strength Graph 14. Graph Flexural Strengths for all mixes
Samples with 10% marble powder had flexural strengths of 84.99 kN, 86.05 kN, and 92.18 kN.Additionally, the increase in flexural strength was proportional to the amount of iron powder employed in the procedure.Despite this, a 1.6% drop can be seen between the control specimen M1 and the WMP 15%-treated specimen M5.Flexural strength was enhanced when marble powder replaced 10% of the cement but was diminished when the proportion was increased to 15%.In addition, M6 (10% marble and 50% iron) was shown to be the greatest replacement ratio for enhancing flexural strength.

Conclusion
Based on the results of the study, it was determined that self-compacting concrete containing marble powder as a replacement for 10-15% of Portland cement outperformed concrete without marble in its composition.The accumulation of marble garbage contributes to environmental pollution, yet this result is helpful because it reduces that pollution.Concrete made using scrap marble is considered "green" concrete since it contributes to a reduction in carbon dioxide emissions from the concrete manufacturing process.It helps keep pollutants at bay and achieves environmental sustainability.Because the presence of such a process creates an environmental problem that cannot be disposed of when not in use, slag, one of the industrial byproducts of the local slag, which until now has been an excess material and there are currently no efforts to use it in industry, was used in the production process.In this experiment, slag was added to concrete by replacing sand at various amounts (30, 40, and 50%).
When marble powder can be collected and repurposed, it is a terrific way to use industrial waste.Larger facilities are encouraged to employ self-compacting concrete made with marble powder to prevent the usual compaction concerns that come with ordinary concrete, reduce expenses, and protect the environment.To decrease environmental damage caused by local slag's occupation of broad regions and to promote its uses, crushing facilities for slag blocks of the correct sizes to be used as aggregates in concrete, roads, and railways must be made available.

Graph 1 .Fig. 1 .
Fig. 1.Mechanical properties of the effect of the marble powder on different mixes

Graph 3 .Graph 4 .
Compressive Strength Raghunath P.N. et al.'s 2019 study on the mechanical and durability properties of marblepowder-based high-strength concrete The specimens S1, S2, S3, S4, and S5 had flexural strengths of 5.7 MPa, 6.1 MPa, 6.8 MPa, 6.2 MPa, and 5.5 MPa, respectively.With a 15% replacement level, a slight decrease was seen.The dearth of available support resources may help to explain this.(2018) (P.N.Raghunath et al.) Flexural strength of different specimens of concrete Raghunath P.N. et al.'s 2019 study on the mechanical and durability properties of marblepowder-based high-strength concrete.Suresh, S. et al., 2019 started yet another study to investigate the viability of using marble powder in the production of concrete.Marble powder will be added to concrete M20 mixtures in varying amounts (0%, 5%, 10%, & 15% by weight) to determine the best replacement percentage.Table 3. Compressive strength for all mixesCompressive strength changes when 5-10% of cement is substituted by marble powder in concrete, according to research by Suresh et al. (2019).S.Suresh et al. (2019).Flexural strength rose even though the specimen NSC dropped by 4.3% compared to the control NSC's 0%.Flexural strength is improved by 5%, 10%, or 15% marble powder in concrete, but decreased by 15%.The graph below demonstrates a clear decline in compressive strength, with NSC 10% and NCS 15% performing the best.Latha et al. (

Graph 6 .Graph 7 .Graph 8 .Graph 9 .
Compressive strength of concrete at 7 & 28 daysIn 2015, G. L. et al. investigated the strength of concrete using discarded marble powder as cementitious material.Waste marble powder increases compression strength ratings for M20, M30, and M40-grade concrete by 10% to 20% at each curing age.Marble powder's calcium carbonate may improve concrete's strength.Marble powder-containing concrete mixes had 5-10% higher early strength.20% replacement concrete has lower compressive strength.The graph below indicates that adding discarded marble powder up to 15% cement weight boosts flexural strength.Waste marble powder reduced the strength of the concrete somewhat.10%-15% marble powder replacement in cement is good.Thus, residual marble powder improves hardened concrete's performance by 15%.ICSTCE 2023 https://doi.org/10.1051/e3sconf/202340503008 E3S Web of Conferences 405, 03008 (2023) Flexural strength for various grades with varying percentages of marble powder KIM, J. et al. (2015), studied the effect of Iron Powder on Inhibition of Carbonation Process in Cementitious in which the iron ore was replaced with different percentages of sand.The paper also shown that the chemical makeup of iron powder is largely the same as that of cement compounds.This classification makes it possible to use iron powder in concrete mixes in place of sand to good effect.Slump con for all mixing ratios of Iron powder Noori, K., et al.'s (2018) studied the mechanical Properties of Concrete Using Iron Waste as a Partial Replacement of sand.The results show that the slump gradually and slightly lessened as iron waste increased.This shows that concrete is workable within a reasonable range and has good durability.(2018) (Noori, K., et al.) ICSTCE 2023 https://doi.org/10.1051/e3sconf/202340503008 E3S Web of Conferences 405, 03008 (2023) Compressive strength with different percentages of waste iron waste.

Figure 2 .
Figure 2. Flowchart of the experimental research

Table 2 .
Percentages of cement and waste marble powder

Table 4
and table5shows the mix design properties and quantities respectively.

Table 4 .
Mix design used in the experiment.