Grafen oksit katkılı yeni nesil harçlarda dozaj ve doğru akım şiddetinin etkilerinin araştırılması

Öz

Çimento esaslı malzemelerde nano-metre boyutundaki malzemelerin kullanılması malzemelere yeni bir vizyon katmaktadır. Grafen oksit; sulu çözeltilerde iyi dağılabilirliği, yüksek özgül ağırlığı, iyi ısıl iletkenliği, esnek yapısı, yüksek görünüş oranı ve mükemmel mekanik özellikleri sayesinde çimento esaslı malzemelerde tercih edilmektedir. Bu çalışmada 250, 300, 350, 400 dozajlı ve su/çimento oranları 0,85 olarak tasarlanmış 4cm x 4cm x 16cm boyutunda harçlar üretilmiştir. Grafen oksit’ in harç fiziksel ve mekanik özelliklerine etkisini araştırmak amacıyla çimento yerine ağırlıkça % 0,025 GO konulan numuneler üretilmiştir. DC gerilimin etkisini araştırmak amacıyla 300 dozajlı harçlar taze halde iken DC güç kaynağı vasıtasıyla 24 saat süresince 15V, 20V, 25V ve 30V gerilime maruz bırakılmıştır. Çalışma kapsamında dozajın; priz bitiş süresine, eğilme dayanımına ve basınç dayanımına etkileri araştırılmıştır. Hidratasyon reaksiyonları başlangıcından itibaren harçların iç sıcaklık değerleri ve yüzeysel nem oranları dakikada bir ölçülmüştür. Harçların fiziksel ve mekanik özelliklerini iyileştirme açısından en uygun dozajın 300 olduğu, en uygun gerilim şiddetinin ise 25V olduğu sonucuna varılmıştır. Harçlara GO konulduğunda harçların iç sıcaklık değerlerinin arttığı, fiziksel ve mekanik özelliklerinin iyileştiği belirlenmiştir. Harçlarda yüzeysel nem oranı ölçülmesi ile priz bitiş süresinin tahmin edilebileceği belirlenmiştir. Çimento yerine hem GO konulması hem de 25V DC gerilim şiddeti uygulanması ile harçların mikro yapısında fark edilir iyileşme gözlenmiştir.

Anahtar Kelimeler

• Harç
• Grafen Oksit
• DC akım
• İç sıcaklık
• Yüzeysel nem

Investigation of the effects of dosage and direct current intensity in new generation mortars with graphene oxide additives

Öz

The use of nano-meter-sized materials in cement-based materials adds a new vision to the materials. Graphene oxide; is preferred in cement-based materials thanks to its good dispersibility in aqueous solutions, high specific gravity, good thermal conductivity, flexible structure, high aspect ratio, and excellent mechanical properties. In this study, mortars with 250, 300, 350, and 400 dosages and a water/cement ratio of 0.85 were produced whose sizes are 4cm x 4cm x 16cm. In order to investigate the effect of graphene oxide on the physical and mechanical properties of mortar, samples containing 0.025 % GO were produced instead of cement. In order to investigate the effect of DC current on 300 dosage mortars; 15V, 20V, 25V, and 30V, stress intensities were applied for 24 hours through the DC power source while the mortars were in a fresh situation. Within the scope of the study, the effects of the dosage on final setting time, flexural strength, and compressive strength were investigated. From the beginning of the hydration reactions, the mortars' internal temperature and surface moisture were measured once per minute. It was concluded that the optimum dosage is 300 in terms of improving the physical and mechanical properties of the mortars, and the optimum stress intensity is 25V. It was determined that when GO was added to the mortars, the internal temperature values of the mortars increased, and their physical and mechanical properties improved. It has been determined the final setting time can be predicted by measuring the surface moisture in mortars. A noticeable improvement was observed in the microstructure of the mortars with the addition GO and the application of 25V DC stress intensity.

Anahtar Kelimeler

• Mortar
• Graphene Oxide
• DC current
• Internal temperature
• Superfical moisture

Kaynakça

1. Referans1 Pacheco-Torgal F., Jalali S., Nanotechnology: advantages and drawbacks in the field of construction and building materials, Constr. Build. Mater., 25, 582–590, 2011. https://doi.org/10.1016/j.conbuildmat.2010.07.009
2. Referans2 Chuah S., Pan Z., Sanjayan J.G., Wang C.M., Duan W.H., Nano reinforced cement and concrete composites and new perspective from graphene oxide, Constr. Build. Mater., 73, 113–124, 2014. https://doi.org/10.1016/ j.conbuildmat.2014.09.040
3. Referans3 Raki L., Beaudoin J., Alizadeh R., Makar J., Sato T., Cement and concrete nanoscience and nanotechnology, Materials (Basel), 3, 918–942, 2010. https:// doi.org/10.3390/ma3020918
4. Referans4 Chintalapudi K., Mohan R., Pannem R., An intense review on the performance of graphene oxide and reduced graphene oxide in an admixed cement system, Construction and Building Materials, 259, 598-618, 2020. https://doi.org/10.1016/j.conbuildmat.2020.120598
5. Referans5 Lu L., Zhao P., Lu Z., A short discussion on how to effectively use graphene oxide to reinforce cementitious composites, Constr. Build. Mater., 189, 33–41, 2018. https://doi.org/10.1016/j.conbuildmat.2018.08.170
6. Referans6 Yazıcı M., Tiyek İ., Ersoy M.S., Alma M.H., Dönmez U., Yıldırım B., Salan T., Karataş Ş., Uruş S., Karteri İ., Yıldız K., modifiye hummers yöntemi̇yle Grafen Oksi̇t (GO) sentezi̇ ve karakteri̇zasyonu, Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji 4(2), 41–48, 2016.
7. Referans7 Chen S.J., Collins F.G., Macleod A., Pan Z., Duan W.H., Wang C.M., Carbon nanotube-cement composites: a retrospect, IES J. Part A: Civil Struct. Eng., 4 (4), 254–265, 2011.
8. Referans8 Phrompet C., Sriwong C., Ruttanapun C., Mechanical, dielectric, thermal and antibacterial properties of reduced graphene oxide (rGO)-nanosized C3AH6 cement nanocomposites for smart cement-based materials, Composites Part B: Engineering, 175, 128-145, 2019. https://doi.org/10.1016/j.compositesb.2019.107128

9. Referans9 Sharma S., Kothiyal N.C., Comparative effects of pristine and ball-milled graphene oxide on physico-chemical characteristics of cement mortar nanocomposites, Construction and Building Materials, 115, 256–268, 2016. https://doi.org/10.1016/j.conbuildmat.2016.04.019
10. Referans10 Korucu H., Şimşek B., Uygunoğlu T., Güvenç A.B., Yartaşı A., Statistical approach to carbon based materials reinforced cementitious composites: Mechanical, thermal, electrical and sulfuric acid resistance properties, Composites Part B: Engineering, 171, 347–360, 2019. https://doi.org/10.1016/j.compositesb.2019.05.017.
11. Referans11 Jing G.J., Ye Z.M., Li C., Cui J., Wang S.X., Cheng X., A ball milling strategy to disperse graphene oxide in cement composites, Xinxing Tan Cailiao/New Carbon Materials, 34(6), 569–577, 2019. https://doi.org/10.1016/S1872-5805(19)60032-6
12. Referans12 Indukuri C.S.R., Nerella R., Madduru S.R.C., Effect of graphene oxide on microstructure and strengthened properties of fly ash and silica fume based cement composites, Construction and Building Materials, 229 (11), 63-68, 2019. https://doi.org/10.1016/j.conbuildmat.2019.116863
13. Referans13 Muthu M., Yang E.H., Unluer C., Resistance of graphene oxide-modified cement pastes to hydrochloric acid attack, Construction and Building Materials, 273, 99-121, 2021. https://doi.org/10.1016/j.conbuildmat.2020.121990
14. Referans14 Akarsh P.K., Bhat A.K., Graphene oxide incorporated concrete for rigid pavement application. In Lecture Notes in Civil Engineering, Springer Singapore, 99, 2021. https://doi.org/10.1007/978-981-15-6828-2_16
15. Referans15 British Standards Institution BSI., Cement - Part 1: Composition, specifications and conformity criteria for common cements BS EN 197-1:2013.
16. Referans16 Marcano D.C., Kosynkin D.V., Berlin J.M., Sinitskii A., Sun Z., Slesarev A., Alemany L.B., Lu W., Tour J.M., Improved synthesis of graphene oxide, ACS Nano, 4 (8), 4806-4814, 2010. https://pubs.acs.org/doi/10.1021/nn1006368
17. Referans17 Alma H., Yazici M., Yildirim B., Salan B., Tiyek I., Coating and characterization of nano-sized graphene on spunbond nonwoven textile surface by electro drawing method, Textile and Engineer, 24 (108), 243–253, 2017. https://doi.org/10.7216/1300759920172410803
18. Referans18 Lu L., Ouyang D., Properties of cement mortar and ultra-high strength concrete ıncorporating graphene oxide nanosheets, Nanomaterials, 7, 187-201, 2017. doi:10.3390/nano7070187
19. Referans19 EN 197-1, Cement—Part 1: Composition, specifications and conformity criteria for common cements; European Committee for Standardization (CEN) Standards: Brussels, Belgium, 2011.
20. Referans20 EN 196-1, Methods of Testing of Cement: Part 1: Determination of strength; European Committee for Standardization (CEN) Standards: Brussels, Belgium, 2016.
21. Referans21 Wade A.S., Nixon J.M., Schindler A.K., Barnes R.W., Effect of temperature on the setting behavior of concrete, J. Mater. Civ. Eng., 22 (3), 214-222, 2010. https://ascelibrary.org/doi/abs/10.1061/%28ASCE%290899
22. Referans22 Moradi F., Hajiloo H., Ghods P., Alizadeh A., Early age electrical resistivity behavior of various concrete mixtures subject to low temperature cycling, Cement and Concrete Composites, 83, 323-334, 2017. https://doi.org/10.1016/j.cemconcomp.2017.07.028
23. Referans23 ASTM International, ASTM C1074-14: Estimating concrete strength by the maturity method, West Conshohocken, PA, 2011.
24. Referans24 Luo Y., Gan Y., Xu J., Yan Y., Shi Y., Effect of electric field intensity and frequency of AC electric field on the small-scale ethanol diffusion flame behaviors, Applied Thermal Engineering, 115, 1330-1336, 2017. https://doi.org/10.1016/j.applthermaleng.2016.11.145
25. Referans25 Kjaernsmo H., Kakay S., Fossa K.T., Gronli J., The effect of graphene oxide on cement mortar, International Conference on Smart Engineering Materials, 362, 120-132, 2018. doi:10.1088/1757-899X/362/1/012012
26. Referans26 İnsapedia, https://insapedia.com/hidratasyon-nedir-hidratasyona-etki-eden-faktorler, 2021.
27. Referans27 Qian Y., Abdallah M.Y., Kawashima S., Nanotechnology in construction. Nanotechnology in Construction, 259–264, 2015. https://doi.org/10.1007/978-3-319-17088-6
28. Referans28 Chintalapudi K., Rao Pannem R.M., Strength properties of graphene oxide cement composites. Materials Today: Proceedings, xxxx, 2020. https://doi.org/10.1016/j.matpr.2020.08.369
29. Referans29 Hu C.L., Han Y.G., Gao Y.Y., Zhang Y.M., Li Z.J., Property investigation of calcium silicate- hydrate (C-S-H) gel in cementitious composites, Mater. Charact., 95 (9), 29–39, 2014. https://doi.org/10.1016/j.matchar.2014.06.012
30. Referans30 Arslan M., Kırgız M.S., Mermer ve tuğla endüstrisi atıklarının çimentoda mineralojik katkı olarak kullanılması, TÜBİTAK Projesi, Proje No MAG-HD15 (105M086), Ankara, 2006.
31. Referans31 Shenghua L., Yujuan Ma., Chaochao Q., Ting S., Jingjing L., Qingfang Z., Effect Of graphene oxide nanosheets of microstructure and mechanical properties of cement composites, Construction And Building Materials, 49, 121-127, 2013. https://doi.org/10.1016/j.conbuildmat.2013.08.022
32. Referans32 Chuanlin H., Microstructure and mechanical properties of fly ash blended cement pastes, Constr. Build. Mater. 73, 618–625, 2014. https://doi.org/10.1016/j.conbuildmat.2014.10.009