The Use of Waste Maroon Marble Powder and Iron Oxide Pigment in the Production of Coloured Self-Compacting Concrete

(is work covers some workability, mechanical, and durability properties of coloured self-compacting concrete (SCC) containing maroon marble powder and iron oxide pigment. Pigments with varying amounts were used to produce coloured SCC. For this purpose, ten different series were prepared of which two of the series were pigment free that one of them was the colour of white SCC including limestone powder and the other one was the colour of maroon SCC including maroon marble powder. (e other series were containing pigments with varying amounts. (e water to binder ratio remained constant for all the series at 0.42. Slump flow, T50 time, V-funnel, and L-box tests were used to determine the workability of coloured SCC.(e hardened properties that were determined included density, water absorption, ultrasonic pulse velocity (UPV), compressive strength, abrasion resistance, and impermeability. As workability, experimental results showed that coloured SCC could be obtained by using maroon marble powder and when iron oxide pigment used in amounts less than 6%.(e addition of pigment notably increased the water absorption of SCC series. (e use of smaller quantities of pigment caused slight increase in compressive strength. Higher pigment content also provided decreases in abrasive resistance, and after exposure to abrasion, mass losses were within the range of 0.89%–2.12% and the abrasion depths were within the range of 0.9mm–2.1mm. Among the varying amounts of pigmented series, M1 series which contains 1% pigment showed the best performance, and the findings indicated that it is possible to successfully utilize maroon marble powder and lower amounts of pigments in producing coloured SCC.


Introduction
As a specially designed concrete, self-compacting concrete (SCC) is a kind of high-performance concrete that can spread in areas of difficult access readily and consolidate into place under its own weight.It can pass through the gaps between the reinforcement bars to fill the formwork completely.SCC also can maintain its stable composition simultaneously without the need of mechanical consolidation and without undergoing any significant separation of material constituents http://www.sciencedirect.com/science/article/pii/S095006181730541X[1][2][3][4].Because of the excellent workability properties of fresh SCC, resulted in good mechanic and durability properties of hardened concrete.Since it was initially developed in Japan in 1980's, SCC got more attention and now SCC has broken fresh ground in modern concrete technology http://www.sciencedirect.com/science/article/pii/S0950061817305354[5].SCC provides a shorter construction time, produces a good surface finish, and provides greater freedom in architectural and aesthetic designs; production of SCC is environmentally friendly because of no noise.SCC is typically associated with low content of coarse aggregates and w/b ratio, and high content of binder, powders, fine aggregates, and plasticizing admixtures.
Architectural concrete is a fantastic topic.Architectural concrete is nonstructural or structural concrete that will be perennially exposed to view and needs special attention for this reason to material uniformity, forming, placing, and finishing to obtain the desired architectural and decorative appearance.Examples of applications are buildings and transportation structures like highway sound/barrier walls, bridges, concrete pavers, concrete roof tiles, pathways, and prefabricated concrete products.Especially in Turkey, concrete parquets are commonly used in urbanization projects for road paving and red-coloured parquets that are used in particular for road marking or road lines can be found along the road or across the road to provide awareness to hazards and to give drivers directions or for rules.Pigments are commonly used for permanent colouring of concrete that is to paint it a colour different from the natural colour of the cement or the various aggregates.
e development of coloured SCC leads to open new areas of application of SCC since it provides attractive alternatives for challenging architectural designs and applications in terms of colour and shapes, to the already all-purpose aesthetic and decorative characteristics of conventional coloured concrete.In addition to the advantages of SCC's fluidity and filling capacity, the coloured SCC enables the aesthetic and decorative aspects from a variety of colours and surface textures.In the literature, some recent applications of coloured SCC can be found [6].
Marble has been used as an architectural decoration to embellish the floors, walls of temples, and public areas since ancient times.It is one of the most widely used decorative and aesthetic pleasing stones all over the world.Turkey has wide resources since it is located in the Alps mountain range, in terms of natural stones.With its 4,000 years of background in marble production, Turkey has been one of the oldest marble producers in the world.Having a remarkable and variety of mineral bases, it has one of the world's largest natural stone reserves and approximately five billion m 3 of valuable marble reserve and has 40% of the world marble potential [7,8].Maroon marble (Elazig cherry) is made of carbonated ultrabasic rocks, serpentinite (Figure 1) and red-green pebbles are attached with the same-coloured cement.
As a by-product of stone crushers, a considerable amount of limestone powder is produced in limestone quarries.Large quantities of powders are accumulated and the use of these by-products has serious problems in terms of environmental pollution, disposal of waste, and public health hazard [9].Additionally, marble manufacturing industry leads to much waste production [10].e waste of maroon marble powder can also cause environmental problem for ecosystem and economic loss if the waste is not recycled, and SCC technology has a great potential for such solid wastes.SCC is one of the most attractive alternatives utilizing the limestone and maroon marble powder in the concrete industry.
e effect of marble powder on the mechanical properties of hardened concrete has been investigated by many researchers, and the use of marble powder in the production of SCC will be expected to become more widespread in the future [11][12][13][14][15][16].
e aim of this study is to investigate the effect of maroon marble powder and iron oxide pigments on the some workability, mechanical, and durability properties of SCC.For this purpose, slump flow, T 50 time, V-funnel time, and L-box ratio tests were performed in terms of workability.Hardened concrete tests were performed such as compressive strength, density, water absorption, and ultrasonic pulse velocity as a performance of maroon marble powder and pigments.Moreover, the abrasion resistance and impermeability of SCC mixtures are investigated.Although these pigments are widely used, a few research has been carried out for the usability of a natural waste (contains no synthetic dyes) to colour the SCC.Experimental results aimed the usability of maroon marble powder as a natural waste in the production of coloured SCC and at recommending optimum amount of pigments for using in the production of SCC in respect to workability, mechanic and durability properties.

Experimental
2.1.Materials.In this study, some materials used include crushed limestone coarse aggregate with the specific gravity of 2.67 and water absorption of 0.24%, a natural river sand with the specific gravity of 2.60 and water absorption of 1.48%, white Portland cement, chemical admixture, and powders.A crushed limestone coarse aggregate and natural river sand, and with a maximum particle size of 16 mm were used as coarse and fine aggregates, respectively.e type of cement used in all SCC series was white Portland cement which is complied with EN 197-1 and labeled as CEM I 52.5 R. 28th day compressive strength and specific surface area by Blaine of cement were 60.0 MPa and 4600 cm 2 /g, respectively.Moreover, limestone powder is used to obtain self-compactability  e total amount of powder was selected to be 600 kg/m 3 , and the water-powder ratio (w/p) was fixed as 0.29 after the preliminary investigations.A 50 dm 3 batch has been prepared for each series.A new generation polycarboxylic ether-based superplasticizer was also used which Advances in Civil Engineering has 1.08 specific gravity, 8.1 pH, and 23.9% solid content.To provide desired fluidity of SCC, superplasticizer was employed at the ratio of 2.06% of binder materials by weight to reduce the water/binder ratio of SCC mixtures.
2.3.Casting, Curing, and Testing of Specimens.Density, water absorption, UPV, and compressive strength measurements were performed on 100 mm cube specimens.Before performing hardened concrete tests, all specimens, with or without pigments, were cured in water at 20 ± 2 °C and 60% RH. e specimens were then cast in molds, and other than their own self-weights were not exposed to any compaction.To analyze some workability properties of SCC mixtures, slump flow diameter, T 50 time, V-funnel time, and L-box ratio tests were performed complied with EFNARC Committee's suggestions [17].Water absorption, compressive strength, and UPV tests were performed on hardened concrete at 3, 7, and 28 days, whereas density was monitored at 28 days.
Water absorption properties of SCC mixtures were achieved according to ASTM C 642-97 Standard [18][19][20] to determine the increased resistance towards water penetration in SCC.Cubic molds, 100 mm in size, were prepared both with and without pigment.After curing, the surfaces of the samples were allowed to dry, and their saturated masses were determined after immersion.For this purpose, the specimens were oven dried at 115 ± 5 °C, and water absorption of the specimens was calculated.
e determination of abrasion resistance was conducted as per specification EN 1338 [21] on cube samples of 71 ± 1.5 mm by using Bohme abrasion test abrader (Figure 2). is standard is highly suggested for the abrasion of concrete paving block applied on SCC specimens to be an alternative of ASTM C779.A great deal of researchers applied this method and achieved reliable results [22][23][24][25].Before the test, the specimens were dried at first to constant mass at a temperature of 105 ± 5 °C.In accordance with this standard, specimens were placed on the steel test disc which is of a 750 mm diameter rotating track, and the specimens were then exposed to grinding for 22 cycles under a constant load of 294 ± 3 N and 30 cycles/min rotation speed.In the test series of steps, before the specimens were placed, standard abrasive of 20 ± 0.5 g was poured on the disc; afterwards, the load was applied to the specimen and the aforementioned procedure was repeated for 16 periods by rotating the sample 90 °in each period that all of them consisting of 22 revolutions.e loss in mass was measured, and the decrease in volume due to abrasion was calculated in cm 3 /cm 2 .Abrasive dust used in this test was artificial corundum.
e water impermeability measurements of SCC mixtures were carried out on three testing specimens using the concrete impermeability test equipment as shown Figure 3, in compliance with German Code DIN-1048 [26].150 mm of standard cube samples were used, and SCC specimens were put on impermeability tester and tubes filled with regular water subsequently.Initially, scale readings of tubes were measured by applying water, and then the samples were placed under pressure and tested up to 1 bar for 24 hours, 3 bars for 24 hours, and 7 bars for 24 hours to determine depth of water impermeability.After that, scale readings accomplished and the weight of the samples and the amount of water absorbed were calculated.At the end of the testing procedure, splitting test was applied on specimens to determine impermeability depth.

Properties of Fresh Concrete.
e slump flow values for SCC with pigments immediately after the mixing process are presented by using the bar graph in Figure 4.Because of the conventional slump test is not appropriate to quantify the workability of SCC, the slump flow is used as a test method for SCC workability [27].All series presented satisfactory flow values of at least 645 mm in terms of workability.By EFNARC, slump flows of 650 mm to 800 mm are typically required for SCC [17].Most of the SCC series were satisfied with EFNARC specifications as satisfactory slump flows in the range of 645-725 mm.
e series which contains pigments with varying amounts performed lower slump flow values than the pigment-free series.As pigment free series, M1 mixture had limestone powder and M1 mixture showed better performance than M2 mixture which contains maroon marble powder for slump flow values.It can be seen from Figure 4 that the results of slump flow tests reveal that in the series which contains larger quantities of pigments there is a further decrease in slump flow values compared to the pigmentfree series.M10 series did not exhibit satisfactory slump flows that are typically required for SCC by the Committee of EFNARC.
is might be explained by the increased  e water content remained constant for all of the series in this study; however, pigment-free series needs less water and provides more slump ow.In terms of workability, the mixtures which contain pigments generally have shown worse performance than the pigment-free series.
e slump ow time for the SCC series was determined by measuring the time taken for the concrete to reach a spread diameter of 500 mm from the moment the slump cone is lifted up for all the series and was less than 5.38 s, and most of the SCC series presented ow time values in the range of 2-5 s as shown in Figure 4 with the dashed line.e T 50 times and the slump ow tests that comply with that of the standard values given by EFNARC [17] were conducted to measure the fresh properties of SCC including lling ability.
Besides of the slump ow and T 50 time, V-funnel test was also employed to assess the stability and owability of the pigment additive series and pigment free series of SCC. e V-funnel ow time values were in the range of 9-18 s.For V-funnel time, EFNARC Committee suggests that 11 s and 15 s for lower and upper limits, respectively, are reasonable for producing the appropriate SCC.In Figure 5, experimental test results revealed that all SCC mixtures do not meet the permitted ow time requirements.erefore, V-funnel time above 15 s would be hard to handle and very cohesive.It can be from Figure 5, that when pigment ratio is increased cohesion of the mixtures are also increased.M1, M2, M3, M4, M5 and M6 series satis ed the suggestion of EFNARC Committee, but other series which contains larger quantities of pigments were very cohesive.It was also observed by other researchers that pigments improve the cohesion of the mortar and concretes [6,28] and the addition of pigments might modify the cohesion and the owability of the mixture.
In the L-box test, the ratio of heights at the two edges of L box, T 400 and T 800 , demonstrates the passing and lling ability of SCC. e sensitivity of blocking is very high in this test method.When the L-box blocking ratio (h 2 /h 1 ) is below 0.8, there can be generally a blocking risk of the SCC mixtures [17].To be considered as an acceptable ratio for designing the functional SCC mixtures, a blocking ratio must be in the range of 0.8-1.00.A maximum particle size of 16 mm coarse aggregate was used in that study keeping away from blocking e ect in this test, and most of the series of SCC have maintained the target range that is in accordance with EFNARC standards.
e blocking ratios of the series of SCCs produced with pigments or the series of without pigments are given in Figure 6. e blocking ratio of the M4 mixture was 0.99, and the blocking ratio of the M10 mixture was 0.78.e yield stress of M10 mixture was high compared with other series because the M10 mixture includes more pigments than the other mixtures.When the pigment content has increased, pigment addition has negatively a ected the blocking ratio due to simultaneous increase in viscosity.Nevertheless, it can be proved in this study that each series examined has adequate passing ability and lling capability in terms of selfcompactibility.

Water Absorption.
For all the mixtures, the hardened properties that were expressed as water absorption, compressive strength, and UPV at 3, 7, and 28 days and the Advances in Civil Engineering density at 28 days.Table 4 report the mean of water absorption as determined from three specimens at three different curing times.As seen in Table 4, water absorption in the specimens submerged in water decreased over time in all the groups.is might have been due to the e ect of the curing environment on SCC properties.e higher water absorption of the series was M10 series which contains the highest amount of pigment, and the use of limestone powder performed positive e ect compared to maroon marble powder additive series.e use of small amount of pigments does not have a remarkable e ect on water absorption properties owing to pigment ller e ect.However, by comparing pigment-free specimens submerged in water, it seems that using larger quantities of pigments can increase water absorption of the SCC specimens.e increase in water absorption as the amount of pigment increases can explain inert e ect of higher amounts of pigments, thus suggesting a system with a high void content, generated by the bad formation of the cementitious matrix owing to the insu cient hydration.But, all specimens satis ed the range of water absorption speci ed in ASTM Standard C 642-97 [18].As seen in Figure 7, specimens amended with maroon marble powder exhibited higher compressive strengths at all curing ages than the larger quantities of pigmented series.For example, the compressive strength of the 7-day specimen of M2 series is about 59.35 MPa, which improves by 25% than those of the M10 series which contains the highest amount of pigment.However, M3 and M4 series that showed the highest performance at all the curing ages were containing less pigments, and this might be attributed that the use of less pigment a ected the performance of SCC in positive way as ller e ect.e decrease in compressive strength of the specimens containing larger quantities of pigments is probably owing to deposition of pigments in the interface between the coarse aggregates and the matrix.e use of higher amounts of pigments weakens the interface between the coarse aggregates, and the matrix acts as inert ller.e other reason of decrease in compressive strength is probably due to a high speci c surface area of the pigment which is used in this study, and the water content remained constant for all of the series.

Compressive
is suggests that, within the cementitious composite, its particles adsorb water.e concrete in question is classi ed as dried and has a low water-cement ratio, having naturally low water availability for hydration reactions of cement's silicates and aluminates.us, the addition of pigment becomes actually detrimental to the compressive strength gain system, as it further reduces even more the water availability for these reactions [29].López et al. investigated advantages of mortarbased design for coloured SCC and observed that SCC mixtures made with pigments have lower compressive strength than those made with pigment-free mixture (reference mixture) [6].Karaguler and Sungur found that using of larger quantities of pigments decreased compressive strength of coloured SCC irrespective of the pigments used in di erent types or di erent amounts [30].Similar results on the decrease of compressive strength by using pigments were reported by other researchers [29,31].Results of this study presented that although the use of larger quantities of pigments decreases the compressive strength, however, the use of small quantities of pigment causes slight increase in compressive strength.5 shows density and UPV values of SCC series.e trend in compressive strength is similar to that in UPV.ere was a simultaneous development that UPV values increased as

6
Advances in Civil Engineering compressive strength values increased for all the series.As a general acceptance, UPV can be used to evaluate the internal structure of concretes nondestructively.Experimental test results proved that there was a very strong correlation between UPV and the compressive strength of SCC series.Correlation coefficient of R 2 was found to be in the order of 95%.e sound transmission velocity is a function of the density of the material in compliance with the sound propagation theory of solids [32], and it is observed that there is a concurrent development between UPV and density as well as compressive strength.Abrasion resistance test results demonstrated that the mass loss rate of SCC gradually increased with the increasing of pigments.Generally speaking, slightly higher resistance to wear was displayed by the pigment-free series of SCC.It is obvious that SCC series having higher compressive strength, in general, possessed lower abrasion values.It was also examined by other researchers that there was a direct correlation between abrasion resistance and compressive strength [33][34][35][36][37].However, when compared to the pigment-free series, the use of larger quantities of pigment also provided decrease in abrasive resistance.

Properties of
e decrease in abrasion resistance might be attributed to providing the formation of less dense and more porous microstructure system in SCC when larger quantities of pigments are used through its chemical and physical effects both during the fresh and hardened states.So, it becomes critical for abrasion resistance of SCC series due to the formation of less dense and more porous microstructure character.

Impermeability.
A measure of the resistance of SCC series against the water impermeability is calculated by the impermeability test by applying pressure over a period of 72 hours.By obtaining the average of three specimens, the maximum depths of water penetration for pigment-free and pigment additive SCC mixtures are given in Table 7.
Table 7 presents that SCC mixtures yielded a water impermeability depth of 4.47-7.28mm. e results reported that M8 series performed the lowest water impermeability Advances in Civil Engineering depth.Furthermore, in the case of using higher amounts of pigments, the increase in the pigment amount has also decreased impermeability depth slightly.Nevertheless, all the series did not allow passing water due to filler effect by filling the pores.Pigments are commonly used to produce coloured SCC, and iron oxide pigment can also be used to slightly reduce the water impermeability and water absorption properties of concrete by filling the pores.Improvements were noted at all the series, clearly demonstrating that using a higher amount of pigment is slightly making the coloured SCC less impermeable.8 illustrates a sample of each series which were produced for this study altogether.By observing Figure 8, a comprehensive visual inspection was performed to evaluate the performance of the pigments used in varying amounts in terms of colour intensity and on the usability of maroon marble powder as a natural waste which contains no synthetic dyes to colour the SCC.SCC series was compared in terms of colour intensity visually.To achieve a slightly similar colour intensity, relative tinting power was evaluated by comparing the iron oxide red pigment and maroon marble powder.Figure 8 shows the variation of colour parameters of hardened SCC series and slump flow  8

Visual Inspection. Figure
Advances in Civil Engineering spread diameter of some fresh SCC series.When the pigment content decreased, there can be seen a lightness on the surface of hardened SCC series.e use of larger quantities of synthetic iron oxide pigments increased colour intensity and tinting power of SCC mixtures.M2 mixtures exhibited more colour intensity compared to M3, M4, and M5 series visually.

Conclusions
is study summarizes an extensive experimental program on coloured SCC by using maroon marble powder as a natural dying agent and varying amounts of pigments.Some conclusions can be drawn from the experimental results: (i) In terms of workability, most of the series of SCC have maintained the target range that is in accordance with EFNARC standards.(ii) e higher water absorption of the series was containing the highest amount of pigment.(iii) e use of small amount of pigments causes slight increase in compressive strength when compared to that of pigment-free series.(iv) SCC mixtures yielded a mass loss of 0.89%-2.12% and yielded an abrasion depth of 0.9 mm-2.1 mm at the end of abrasion wear test at 28 d.(v) SCC mixtures yielded a water impermeability depth of 4.47-7.28mm, and all the series of SCC's did not allow passing water through concrete.
e results presented in this paper reveal that it is possible to successfully utilize maroon marble powder in producing coloured SCC and pigments used in amounts more than 3% generally do not improve coloured SCC properties.

Figure 7 :
Figure 7: Compressive strength of SCC series at varying times.

Table 1 :
Mechanical, physical, and chemical properties of cement and mineral admixtures.

Table 2 :
Physical and chemical properties of pigment.

Table 3 :
Mix proportions of SCC mixtures.

Table 4 :
Water absorption values of SCC series.
12% at 28 days.As seen in Table6, M1 series showed the best and contained both the lowest mass loss values and lowest abrasion depth values when compared with other SCC series at 7 d and 28 d.It was also noticed that mass loss values and abrasion depth values reduced as the curing time increased for all SCC series.Experimental test results expressed that the abrasion resistance of SCC was positively affected by curing time which contains maroon marble powder and pigmented series which contains varying amounts of iron oxide pigments.

Table 6 :
Abrasion depths and mass losses of SCC series.

Table 5 :
UPV and density of the SCC series.

Table 7 :
Water impermeability depths of SCC series.