Microsoft Word - Manuscript.doc 22 JOURNAL OF ENGINEERING RESEARCH AND TECHNOLOGY, VOLUME 5, ISSUE 2, JUNE 2018 Utilization of Waste Iron Powder as Fine Aggregate in Cement Mortar Bassam A. Tayeh1 Doha M. Al Saffar2 1Civil Engineering Department, The Islamic University of Gaza, Gaza, Palestine, btayeh@iugaza.edu.ps 2Civil Engineering Department, Al Mansour University College, Baghdad, Iraq, doha.mothefer@muc.edu.iq Abstract— This paper reports about the use of recycled iron powder (IP) in producing cement mortar under normal conditions. Flow table test was performed on fresh mortar. Destructive tests were conducted on cubes of the hardened mortar to obtain the compressive and flexural strengths of the cement mortar. The effects of adding 10%, 20%, 30%, and 40% of waste IP as a natural sand replacement were assessed and compared. Waste iron are of two types: iron IP, which shows a similar particle size distribution to that of the sand used in making the samples, and fine iron powder (FIP), which contains fine particles. The compressive strength decreased with the increased amount of added IP in the mixtures, but it increased with the addition of 10% FIP and decreased gradually with the increased FIP level. By contrast, the flexural strength significantly increased with increased FIP in the mixtures. Recommendations regarding the applications of recycling to conserve resources and raw materials and prevent environmental pollution are provided. Index Terms— Recycled materials, iron powder, waste materials, green product I INTRODUCTION Concrete is currently the most widely used construction material worldwide; its numerous applications include that in bridges, dams, house constructions, highway pavements, and sidewalks [1]. The use of manufactured fine aggregates has been increasing in the United States because good-quality natural sand is not economically viable in many areas. Manufactured fine aggregates differ from natural sand in terms of grading, particle shape, and texture [2]. Research and field experience have shown that good- quality concrete with proper workability and finishabil- ity can be realized using manufactured fine aggregates [3,4]. Various image analysis techniques [5,6] have been used to determine the shape and texture of aggre- gates. The increasing amount of waste iron in the Gaza Strip is one of the major environmental issues in Gaza. The large amount of wastes originates from the industrial sector. These wastes are deposited in landfills. The pre- sent study investigated the utilization of the large amount of iron waste from workshops, factories, and demolished buildings in building construction. Conse- quently, new opportunities will be created with the use of new material in construction, thereby improving many of the overall building parameters. Moreover, the shortage of natural sand in several areas has been in- creasing annually [7-12]. In recent years, commonly recycled materials can be used for either building con- structions or road repairs, such as that of asphalt pav- ing. These materials include wood, gypsum wallboard, building concrete, and metals. Thus, in this study, waste iron powder (IP) was reused as a partial sand replace- ment in a mortar mixture to achieve higher compressive strengths and flexural strengths than those with stand- ard mortar mixes [7-13]. The municipal waste components in Gaza City consist of organic matter (57%), paper and cardboard (15%), plastics (15%), iron metal (4%), glass (3%), and other materials (6%), as shown in Fig. 1. This study mainly aimed to evaluate the use of waste IP in cement mortar mixtures and its effects on their prop- erties. This objective was achieved as follows: first, the effects of adding different percentages of waste were examined and compared with that of a conventional mixture. Afterward, the optimum percentage of waste IP added to the mortar mixture to enhance its properties was determined. This study also aimed to evaluate the effects of using waste IP as a part of the solution for environmental catastrophes resulting from disposal. The cement mor- tar performance was improved by using waste IP as a sand replacement in the mixture. Bassam A. Tayeh and Doha M. Al Saffar/Utilization of Waste Iron Powder as Fine Aggregate in Cement Mortar (2018) 23 Figure 1 Municipal waste components II Experimental Investigation A - Testing program The compressive and flexural strengths were deter- mined on 50 mm cubic specimens, [14] with dimen- sions of 1.6 in×1.6 in×6.3 in or 4 cm×4 cm×16 cm, respectively [15]. A total of 69 cubes were used for the compression test. Three cubes were utilized for each percentage at 7, 28, and 54 days. Fifteen prisms were used for the flexural test, with three cubes for each per- centage for 28 days only. B - Material and mixture proportion Portland cement type I 42.5 N was used to complete all the mortar mixtures [16]. The chemical compositions are provided in Table 1. Two types of waste IP were utilized: IP, which showed the same size as the sieve analysis of sand [17], and fine IP (FIP), which was passed through a 1.18 mm sieve and retained on sieve #200, as shown in Figs. 2. The measured size distribu- tions are presented in Table 2 and Fig. 3. Nine mortar mixtures were cast, of which one was a conventional mixture, four were IP, and four were FIP. Three specimens were evaluated for each test, and the mean values were reported. The mixture proportions are given in Table 3. This study considered different amounts of waste IP (0%, 10%, 20%, 30%, and 40%) as sand replacement. Figure 2 Waste iron pwoder used in this study Table 1 Chemical and physical properties of cement Chemical properties Oxides composition Content % Lime, CaO 66.07 Silica, SiO2 19.01 Alumina, Al2O3 4.68 Iron oxide, Fe2O3 3.2 Magnesia, MgO 0.81 SO3 1.17 Lime Saturation Factor, (L.S.F) 1.08 Physical properties Specific surface area (Blaine method), (cm2/g) 2900 Min. 2800 Setting time (vicate apparatus) Initial setting, hrs. : min Final setting, hrs. : min 2:15 3:30 Not less than 45 min Not more than 10 hrs Compressive strength (MPa) For 3-day For 7-day 20.4 28.2 Not less than 15 MPa Not less than 23 MPa Water demand 0.26 % No limit Bassam A. Tayeh and Doha M. Al Saffar/Utilization of Waste Iron Powder as Fine Aggregate in Cement Mortar (2018) 24 Table 2 Physical properties of fine aggregate and Iron Powder Figure 3 Grading curves of aggregates Table 3 Mixture composition of all experiment series, kg/m3 Mixture ID Cement Sand IP FIP % of replacemen w/c Water Flow (mm) MR 500 1500 - - - 0.5 250 193 MIP1 500 1350 150 - 10 0.5 250 187 MIP2 500 1200 300 - 20 0.5 250 186 MIP3 500 1050 450 - 30 0.5 250 185 MIP4 500 900 600 - 40 0.5 250 183 MFIP1 500 1350 - 150 10 0.5 250 190 MFIP2 500 1200 - 300 20 0.5 250 186 MFIP3 500 1050 - 450 30 0.5 250 187 MFIP4 500 900 - 600 40 0.5 250 176 III Experimental Results and Discussion A - Fresh properties Effects of IP and FIP as aggregate replacements: As shown in Fig 4., the mixtures generally showed a low flow with increased percentages of IP and FIP, which resulted in low fluidity, especially for MFIP4. Flow table test results [12] revealed a reduction in diameter with increased waste IP compared with the reference mixture; the reduction was approximately 2.95%, 3.73%, 4.41%, and 5.44% for MPI1, MPI2, MPI3, and MPI4 mixtures, respectively. The reduction in FIP di- ameter was about 1%, 3.1%, 3.4%, and 9.6% for MFIP1, MFIP2, MFIP3, and MFIP4, respectively, as shown in Fig 4. This trend may be due to the heteroge- neity and angularity of waste IP, which was consistent with that reported by Ismail [7]. Figure 4 Effect of IP and FIP replacement on flowability cement mortar B - Hardened properties Figs. 5–7 show the variability (standard deviations as error bars) in hardened density, compressive strength, and flexural strength, respectively, of different mixtures. Table 5 presents the detailed results. Effects IP and FIP as aggregate replacements on hardened density: The specimens made with IP and FIP displayed Physical properties Property Fine aggr gate IP Specification Specific gravity 2.884 6.584 ASTM C127-04 [11] Absorption, % 39 - ASTM C127-04 Dry loose unit weight, gm/cm³ 1.596 - ASTM 29/C29M/02 Dry rodded unit weight, gm/cm³ 1.742 - ASTM 29/C29M/02 Bassam A. Tayeh and Doha M. Al Saffar/Utilization of Waste Iron Powder as Fine Aggregate in Cement Mortar (2018) 25 higher densities than that of the MR mixture. This differ- ence can be attributed to that the waste IP possessed a 2.28 times higher specific gravity (SG) than that of the sand. The unit weight of cement mortar increased with the in- corporation of IP as aggregate replacement. Such replace- ment by FIP also decreased the air content, which conse- quently increased the unit weight of mixtures. Effects of IP and FIP as aggregate replacements on com- pressive strength: The compressive strength decreased with the increased IP percentage. The reduction in MIP1 was 2.17%, 6.45%, and 6.69% after 7, 28, and 54 days, respectively. The corresponding values after 7, 28, and 54 days were 16.6%, 21.9%, and 33.3% for MIP2; 13.56%, 25.97%, and 42.3% for MIP3; and 10%, 17.7%, and 28.76% for MIP4, respectively. The compressive strength of the MFIP1 mixture increased by 10.14% and 10.17% after 7 and 28 days, respectively. This trend may be due to the high density and strength of the waste IP, which was consistent with the findings in [18]. The percentage of increment was 6% for 28 days. The compressive strength of MFIP2 after 7 days was nearly the same as that of the MR mix, but a small reduc- tion of 4.48% was observed after 28 days. MFIP3 and MFIP4 showed significant reductions of 2.42% and 11.19% after 7 days and 10.37% and 11.17% after 28 days, respectively. These reductions may be attributed to the small voids appearing on the internal texture of the specimen after failure in the compression test or the high percentage of IP, which may affect the hydration process of cement and consequently reduce the strength [7]. The optimum percentage of FIP replacement was obtained at 10% with an increase of 10.14% and 10.17% after 7 and 28 days, respectively, compared with the reference mix- ture. Table 5 Hardened properties Mixture I Density, kg/m3 Compressive strength, MPa Flexural Strength, MPa 7 days 28 days 7 days 28 days 54 days 28 days MR 2470 2480 27.6 33.92 39.87 4.07 MIP1 2560 2590 27 31.73 37.2 4.12 MIP2 2640 2640 23.76 29.32 35.87 4.63 MIP3 2670 2720 21.53 25.11 32.8 4.68 MIP4 2760 2760 18.4 22.23 28.4 4.82 MFIP1 2478 2480 30.40 37.37 - 4.65 MFIP2 2520 2570 27.51 32.40 - 4.93 MFIP3 2680 2720 26.93 30.40 - 4.94 MFIP4 2790 2810 24.51 30.13 - 5.21 Bassam A. Tayeh and Doha M. Al Saffar/Utilization of Waste Iron Powder as Fine Aggregate in Cement Mortar (2018) 26 Figure 1 Effect of waste iron powder on hardended density at different age Figure 2 Effect of waste iron powder on compressive strength at different age Figure 7 Effect of waste iron powder on flexural strength at different age. Failure occurred during compression test on the specimens, and voids appeared on the internal surface texture of the specimen. The number of voids increased with the in- creased waste IP percentage. Thus, the reduction in the compressive strength may be attributed to this phenome- non, as shown in Fig. 8. Effects of FIP as aggregate replacement on flexural strength: The preceding table and Figs. 8 and 9 show that the flexural strength increased with increased FIP percent- age compared with that of the reference mixture. The MFIP4 mixture presented the highest flexural strength, which was 14.83% higher than that of the MR mixture. These results were consistent with those reported in [7,18]. The highest flexural strength was that of the MFIP2 mix- ture after 28 days; the value was 27.86% higher than that of the reference mixture at the same curing period. IV Conclusions According to the present findings, the following conclu- sions can be drawn: The cost showed no increase when waste IP-modified mor- tar mix was used compared with that using conventional mortar mix. Flow test result revealed a reduction in diameter with in- creased waste compared with that of the reference mix. The dry densities of the cement mortar specimens with 10%, 20%, 30%, and 40% IP and FIP were higher than that of the reference mix. The compressive strength decreased with increased IP per- centage. When 10% IP was added in the mixture, the com- pressive strength decreased by 2.17%, 6.45%, and 6.69% after 7, 28, and 54 days, respectively, compared with the control mixture. The corresponding values when adding 20%, 30%, and 40% IP decreased: 16.6%, 21.9%, and 33.3% after 7 days; 13.56%, 25.97%, and 42.3% after 28 days; 10%, 17.7%, and 28.76% after 54 days. The cement mortar mix modified with 10% IP increased by 10.14% after 7 days and 10.17% after 28 days. With the addition of 20% FIP, the compressive strength after 7 days was nearly the same as that of the reference mix, and a small reduction of 4.48% was detected after 28 days. With the addition of 30% and 40% FIP, significant reductions of 2.42% and 11.19% after 7 days and 10.37% and 11.17% after 28 days were observed. Figure 8 Specimens under flexural and compres- sive stress Bassam A. Tayeh and Doha M. Al Saffar/Utilization of Waste Iron Powder as Fine Aggregate in Cement Mortar (2018) 27 The flexural strength increased with increased FIP percent- age. The specimens with 40% FIP showed the highest flex- ural strength, which was 14.83% higher than that of the reference mix. Acknowledgement The authors are grateful to the staff of the Islamic Universi- ty of Gaza (IUG) Soil and Materials Lab for their help dur- ing the sample preparation and testing. Special thanks are directed to senior civil engineering students, Feras Emad Al-Khozondar, Mahmoud Adnan AlBuhaisi, Mohammed Bassam Alqady and Suliman Mohammed Alagha for help- ing the authors in carrying out the experimental program. References [1] Shehdeh,G., HusamN., and RosaV.,"Experimental study of concrete made with granite and iron powders as partial replacement of sand", Sustainable Materials and Technolo- gies, Volume 9, September 2016, Pages 1-9. [2] Quiroga, P. N., Ahn, N., & Fowler, D. W. (2006). Con- crete mixtures with high microfines. ACI materials journal, 103(4), 258. [3] De Larrard, F. (2014). Concrete mixture proportioning: a scientific approach. CRC Press. london, 320pp. [4] Bigas, J. P., & Gallias, J. L. (2002). Effect of fine min- eral additions on granular packing of cement mixtures. Magazine of Concrete Research, 54(3), 155-164. [5] Kim, H., Haas, C. T., Rauch, A. F., & Browne, C. (2002). Dimensional ratios for stone aggregates from three- dimensional laser scans. Journal of computing in Civil En- gineering, 16(3), 175-183. [6] Kuo, C. Y., Frost, J., Lai, J., & Wang, L. (1996). Three- dimensional image analysis of aggregate particles from orthogonal projections. Transportation Research Record: Journal of the Transportation Research Board, (1526), 98- 103. [7] Ismail Z. Z. and AL-Hashmi E. A., “Reuse of waste iron as a partial replacement of sand in concrete,” Waste Man- agement, vol. 28, no. 11, 2008, pp. 2048–2053. [8] Bassam A. Tayeh, (2018) Investiga- tion the effect of marble, timber and glass powder as a parti al replacement of cement. Journal of Civil Engineering and Construction 7, 02, 63-71. [9] Zhao S., Fan J., and Sun W., “Utilization of iron ore tailings as fine aggregate in ultra-high performance con- crete,” Construction and Building Materials, vol. 50, pp. 540–548, 2014. [10] Alwaeli and J. Nadziakiewicz, “Recycling of scale and steel chips waste as a partial replacement of sand in concrete,” Construction and Building Materials, vol. 28, no. 1, pp. 157–163, 2012. [11] Ahmed S.O., Hamdy A. Abdel-G., " The effect of re- placing sand by iron slag on physical, mechanical and radi- ological properties of cement mortar", HBRC Journal, Vol- ume 13, Issue 3, December 2017, Pages 255-261. [12] ASTM C109 / C109M - 2013e1, "Standard Test Method for Compressive Strength of Hydraulic Cement Mortars (Using 2-in. or [50-mm] Cube Specimens) ", American Society for Testing and Materials Standard Prac- tice. [13] ASTM C 348 – 2002, "Standard Test Method for Flexural Strength of Hydraulic-Cement Mortars", American Society for Testing and Materials Standard Practice C348. [14] ASTM C150, "2004, Standard specification of Port- land cement" American Society for Testing and Materials Standard Practice. [15] ASTM C566, 2004,"Standard Test Method for Bulk density (" Unit weight") and Voids in aggregate", American Society for Testing and Materials Standard Practice C566. [16] ASTM C127-C128, 2004, "Standard Test Method for Specific gravity and absorption of fine aggregate”, Ameri- can Society for Testing and Materials Standard Practice C128. [17] ASTM C230/C230M, 2008," Standard Specification for Flow Table for Use in Tests of Hydraulic Cement1", American Society for Testing and Materials Standard Prac- tice C230. [18] Ali N. Alzaed1, "Effect of iron filling in concrete com- pressive and tensile strength" International Journal of Re- cent Development in Engineering and Technology, Volume 3, Issue 4, October 2014) Pages 121-125. Bassam A. Tayeh is Assistant Professor at Civil Engineer- ing Department at Islamic University of Gaza (IUG), Gaza, Palestine. Currently he is Manager of Iwan Center of the Engineering Department at Islamic University of Gaza. Since 2015 to date he is a president of the Engineers Asso- ciation at North Gaza Governorate – Palestine. He has an extensive experience in both academic and practice in many fields of civil engineering, he has published many papers in international journals with high impact factors. He was a presenter at several international conferences. He is a reviewer for many international journals. Email btayeh@iugaza.edu.ps ORCID: http://orcid.org/0000-0002-2941-3402 Doha M. Al-Saffar is an assistant lecturer of Civil Engi- neering at Al- Mansour University College. She received her BSc in 2009 from University of Technology/ Building and Construction Engineering Department; her MSc in 2012 from the University of Technology, Iraq. She has the appropriate expertise to judge building materials. Her re- search interests include lightweight concrete, using recy- cled materials in concrete, Fiber reinforced concrete. She has many years' experience of teaching at al Mansour Uni- versity College in Civil Engineering department. Email- doha.mothefer@muc.edu.iq ORCID: http://orcid.org/0000-0002-8580-2672