Influence of graphene oxide additions on the microstructure and mechanical strength of cement
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摘要: 研究了不同掺量下氧化石墨烯(GO)对水泥石以及胶砂微观结构和力学性能的影响。含16.5%水的水泥浆、0.05%GO及3倍于水泥的沙子共混物作为添加剂制备成砂浆。通过SEM、液氮吸附仪和一系列标准实验分别对水泥石的微观形态、孔隙结构、抗压抗折强度以及水泥净浆的流动度、黏度、凝结时间进行表征;考察不同GO掺量下水泥水化放热的变化情况。结果表明:GO对水泥浆有显著增稠和促凝作用;GO的掺入可以有效降低水泥的水化放热量;GO对水泥石有显著的增强增韧效果,28天龄期时,GO质量分数为0.05%的水泥石,3、7和28 d抗压强度和抗折强度同比对照组分别增加52.4%、46.5%、40.4%和86.1%、68.5%、90.5%,胶砂的抗压强度和抗折强度同比对照组分别增加43.2%、33%、24.4%和69.4%、106.4%、70.5%;GO在水泥硬化过程中对水泥石中晶体产物的产生有促进作用并能规整晶体的排布而形成针状晶体簇,改善水泥石中的孔结构,降低水泥石中微孔的体积,增加水泥石的密实度,对水泥石有显著地增强增韧效果。Abstract: The effect of adding graphene oxide (GO) to cement on its microstructure and mechanical strength was investigated. A paste of cement (16.5% of water)and GO (0.05%) was prepared together with an identical mixture to which sand (3x the weight of the cement) had been added to form a mortar. The fluidity, viscosity and setting time of the mortar and the morphology, pore structure and compressive and flexural strengths of both the hardened cement paste and mortar, were investigated using SEM, nitrogen adsorption, and fluidity, viscosity, mechanical and hydration tests. The influence of the GO addition on the hydration heat of the cement was also tested. Results show that the addition of GO increases the viscosity, decreases the fluidity and shortens the setting time of the mortar. It also reduces the heat of hydration of the cement. The compressive and flexural strengths of the hardened cement paste at different times are increased by the addition of GO. The flexural strength was greater by 86.1%, 68.5% and 90.5% after 3, 7 and 28 days, respectively, and the corresponding compressive strength increases were 52.4%, 46.5% and 40.4% For the hardened mortar, the corresponding increases are 69.4%, 106.4% and 70.5% for flexural strength and 43.2%, 33% and 24.4% for compressive strength. The addition of GO promotes hydration, decreases pore volume, accelerates crystallite formation and causes the crystallites to align, which increases the tightness of both the hardened cement paste and mortar.
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Key words:
- Graphene oxide /
- Cement composites /
- Reinforcing and toughening /
- Microstructure /
- Hydration heat
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Tang J H, Cai J W, Zhou M K. The status of researching and developing in high performance concrete
[J]. Science and Technology of Overseas Building Materials, 2006, 27(3): 11-15.
Boulekbache B, Hamrat M, Chemrouk M, et al. Influence of yield stress and compressive strength on direct shear behaviour of steel fibre-reinforced concrete
[J]. Construction and Building Materials, 2012, 27(1): 6-14.
Sun M, Liu Q, Li Z, et al. A study of piezoelectric properties of carbon fiber reinforced concrete and plain cement paste during dynamic loading
[J]. Cement and Concrete Research, 2000, 30(10): 1593-1595.
Chung D D L. Carbon materials for structural self-sensing, electromagnetic shielding and thermal interfacing
[J]. Carbon, 2012, 50(9): 3342-3353.
Luo J L, Duan Z D, Zhao T J, et al. Hybrid effect of carbon fiber on piezoresistivity of carbon nanotube cementbased composite
[J]. Advanced Mater Res, 2011, 143-144(1): 639-643.
Bahar D, Salih Y. Thermoelectric behavior of carbon fiber reinforced light weight concrete with mineral admixtures
[J]. New Carbon Materials, 2008, 23(1): 21-24. (Bahar D, Salih Y. 炭纤维增强轻质矿粉泥混土的热电行为
[J]. 新型炭材料, 2008, 23(1): 21-24)
Li H, Xiao H G, Ou J P. Effect of compressive strain on electrical resistivityof carbon black-filled cement-based composites
[J]. Cement and Concrete Composites, 2006, 28(9): 824-828.
Chung D D L. Electrically conductive cement-based materials
[J]. Advances in Cement Research, 2004, 16(4): 167-176.
Li K Z, Wang C, Li H J, et al. Development and study of carbon fiber reinforced cement composites
[J]. Materials Review, 2006, 20(5): 85-88.
Li G Y, Wang P M. Microstructure and mechanical properties of carbon nanotubes cement matrix composites
[J]. Journal of The Chinese Ceramic Society, 2005, 33(1): 105-108.
Lao Y S, Zhang L, Wang X P, et al Research progress in effect of nanoparticles on the performance of cement-based materials
[J]. Materials Review, 2014, 28(3): 93-96.
YANG Quan-hong. Dreams may come: from fullerene,carbon nanotube to graphene
[J]. New Carbon Material, 2011, 26(1): 1-4. (杨全红. "梦想照进现实"——从富勒烯、碳纳米管到石墨烯
[J]. 新型炭材料, 2011, 26(1): 1-4.)
Du H J, Pang S D. Transport of water and chloride ion in cement composites modified with graphene nanoplatelet
[J]. Key Engineering Materials, 2015, 629-630(1): 162-167.
Yang Y G, Chen Ch M, Wen Y F, et al. Oxidized graphene and graphene based polymer composites
[J]. New Carbon Materials, 2008, 23(3): 193-200. (杨永岗, 陈成猛, 温月芳, 等. 氧化石墨烯及其与聚合物的复合
[J]. 新型炭材料, 2008, 23(3): 193-200.)
Chen C M, Yang Q H, Yang Y G, et al. Self-assembled free-standing graphite oxide membrane
[J]. Adv Mater, 2009, 21(29): 3007-3011.
Nawa M N A T. Effect of fly ash on the kinetics of portland cement hydration at different curing temperatures
[J]. Cement and Concrete Research, 2011, 41(6): 579-589.
Snelson D G, Wild S, O'Farrell M. Heat of hydration of Portland Cement-Metakaolin-Fly ash (PC-MK-PFA) blends
[J]. Cement and Concrete Research, 2008, 38(6): 832-840.
Langan B W, Weng K, Ward M A. Effect of silica fume and fly ash on heat of hydration of Portland cement
[J]. Cement and Concrete Research, 2002, 32(7): 1045-1051.
ZENG Q, LI K, FEN-chong T, et al. Pore structure characterization of cement pastes blended with high-volume fly-ash
[J]. Cement and Concrete Research, 2012, 42(1): 194-204.
Provis J L, Myers R J, White C E, et al. X-ray microtomography shows pore structure and tortuosity in alkali-activated binders
[J]. Cement and Concrete Research, 2012, 42(6): 855-864.
Neithalath N, Sumanasooriya M S, Deo O. Characterizing pore volume, sizes, and connectivity in pervious concretes for permeability prediction
[J]. Materials Characterization, 2010, 61(8): 802-813.
Constantinides G, Ulm F. The effect of two types of C-S-H on the elasticity of cement-based materials: Results from nanoindentation and micromechanical modeling
[J]. Cement and Concrete Research, 2004, 34(1): 67-80.
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