Dynamic mechanical properties and microscopic mechanism of graphene oxide modified coral mortar under impact load
-
摘要: 珊瑚砂是我国南海岛礁应急工程的首选建筑材料，但因其具有疏松多孔、强度低、易破碎等缺陷，珊瑚砂浆的整体力学性能难以满足设计要求。氧化石墨烯(GO)可有效改善珊瑚砂浆的力学性能，然而，目前关于冲击荷载作用下GO改性珊瑚砂浆的动态力学特性研究少有涉及。本文通过开展改性珊瑚砂浆的冲击压缩试验与微观结构试验，分析了不同氧化石墨烯掺量和不同应变率条件下改性珊瑚砂浆动态力学性能的变化规律及其微观机制。结果表明：(1) 珊瑚砂浆的动态应力-应变曲线近似呈四段式，其变化趋势受GO掺量和应变率影响显著；(2) 在相同应变率条件下，珊瑚砂浆的动态抗压强度随GO掺量的增加均呈先增加后降低的变化特征，且在GO掺量为0.03wt%时达到最大值；(3) 珊瑚砂浆的动态增强因子(DIF)和韧性指数具有明显的应变率效应；(4) GO可定向驱使水化产物充填砂浆裂隙或孔隙，提高结构完整性，增强珊瑚砂浆抗冲击性能。Abstract: Coral sand is widely used as a preferred building material for emergency projects of reef islands in the South China Sea. The mechanical properties of coral mortar are normally low due to the loose porosity, low particle strength and easy breakage of coral sand, making it hard to meet the requirements of practical projects. It is well recognized that graphene oxide (GO) can effectively improve the mechanical properties of coral mortar, but limited studies focus on the dynamic mechanical properties of GO-modified coral mortar under impact loads. In this study, a series of impact compression tests and microscopic tests were conducted on GO-modified coral mortar to investigate effects of GO content and strain rate on its dynamic mechanical properties and microscopic behaviors, respectively. Experimental results demonstrate that stress-strain curves of coral mortar could be approximately divided into four stages, and the development patterns of the curves were combinedly influenced by GO content and strain rate. The dynamic compressive strength of GO-modified coral mortar firstly increases and then decreases with increasing GO content, with a maximum value at 0.03wt% of GO content. Also, the dynamic strengthening factor (DIF) and toughness index of GO-modified coral mortar show obvious strain-rate effects. Microstructural observations imply that the addition of GO could drive hydration products to fill the cracks or large pores inside coral mortar, leading to improvements in its structural integrity and impact resistance performance.
-
图 3 不同GO掺量(CGO)下改性珊瑚砂浆的应力-应变曲线及其破坏状态
σmax—Peak stress; εmax—Ultimate strain
Figure 3. Stress-strain curves and failure state images of modified coral mortar samples at various GO contents (CGO)
图 4 不同应变率下GO掺量与改性珊瑚砂浆动态抗压强度的关系
Figure 4. Relationship between GO content and dynamic compressive strength of modified coral mortar at different strain rates
图 5 改性珊瑚砂浆GO掺量、应变率和韧性指数间的变化关系
R2—Correlation coefficient
Figure 5. Relationship between GO content, strain rate and toughness index of modified coral mortar
图 6 改性珊瑚砂浆动态增强因子(DIF)随GO掺量和应变率的变化关系
Figure 6. Variations of dynamic enhancement factor (DIF) with GO content and strain rate for modified coral mortar
图 7 不同GO掺量下珊瑚砂浆的XRD图谱((a)~(c))和水化产物衍射峰分布图(d)
C-S-H—Calcium silicate hydrate; AFt—Ettringite; AFm—Ettringite
Figure 7. XRD spectra of coral mortar with different GO contents ((a)-(c)) and diffraction peak distributions of hydration products (d)
图 8 不同GO掺量下珊瑚砂浆的XRD定量分析结果
Figure 8. XRD quantitative analysis results of coral mortar with different GO contents
图 9 不同GO掺量下珊瑚砂浆的微观结构形态
Figure 9. Microstructural observations of coral mortar with different GO contents
表 1 水泥的化学组成
Table 1. Chemical composition of cement
Composition SiO2 Al2O3 Fe2O3 CaO MgO SO3 Mass fraction/wt% 20.86 5.90 3.61 56.77 3.50 2.43 
下载: 导出CSV
表 2 水泥的基本物理性质
Table 2. Basic physical properties of cement
Density/
(g·cm−3)Specific surface
area/(m2·kg−1)Loss on ignition/wt% Initial setting time/min Final setting time/min 3 d flexural
strength/MPa3 d compressive strength/MPa 3.12 381 1.4 115 184 6.2 33.8
下载: 导出CSV
表 3 不同氧化石墨烯(GO)掺量下改性珊瑚砂浆(CM)试样的组成
Table 3. Composition of graphene oxide (GO) modified coral mortar (CM) samples at different GO contents
Sample GO fraction/wt% Water cement ratio Cement/g Coral sand/g Water/g GO dispersion/g CM 0.00 0.5 110 220 55.0 0.0 0.02%GO/CM 0.02 0.5 110 220 52.8 2.2 0.03%GO/CM 0.03 0.5 110 220 51.7 3.3 0.04%GO/CM 0.04 0.5 110 220 50.6 4.4 0.05%GO/CM 0.05 0.5 110 220 49.5 5.5
下载: 导出CSV
表 4 冲击压缩试验参数
Table 4. Impact compression test parameters
Elasticity modulus
E/GPaWave velocity
C0/(m·s−1)Pressure rod section area
A0/mm2Sample section area
As/mm2Sample thickness
Ls/mm250 5667 1962.5 1962.5 25
下载: 导出CSV
表 5 GO改性珊瑚砂浆的试验结果
Table 5. Test results of GO modified coral mortar
Sample GO mass
fraction/wt%Static
compressive
strength/MPaStrain
rate/s−1Dynamic
compressive
strength/MPaUltimate
strainDIF Toughness
indexCM 0 33.8 69.67 34.82 0.018 1.030 0.511 87.61 43.84 0.013 1.297 0.841 104.46 53.11 0.027 1.571 1.232 0.02%GO/CM 0.02 38.3 73.53 40.23 0.019 1.050 0.624 83.92 51.46 0.022 1.343 0.930 101.96 62.87 0.027 1.642 1.402 0.03%GO/CM 0.03 42.5 71.93 45.04 0.019 1.060 0.691 85.02 57.98 0.022 1.364 1.091 102.54 73.09 0.027 1.720 1.673 0.04%GO/CM 0.04 41.4 72.10 43.64 0.019 1.054 0.684 89.32 54.19 0.024 1.309 0.997 102.82 67.88 0.027 1.640 1.537 0.05%GO/CM 0.05 39.7 70.33 41.43 0.019 1.043 0.617 88.33 52.30 0.023 1.317 1.027 97.63 64.12 0.025 1.615 1.368 Notes: DIF is the dynamic strengthening factor, which is the ratio of dynamic compressive strength to static compressive strength; Toughness index is the area enclosed by the stress-strain curve and the horizontal coordinate.
下载: 导出CSV
-
[1] 汪稔, 吴文娟. 珊瑚礁岩土工程地质的探索与研究—从事珊瑚礁研究30年[J]. 工程地质学报, 2019, 27(1):202-207.WANG Ren, WU Wenjuan. Exploration and research on engineering geological properties of coral reefs—Engaged in coral reef research for 30 years[J]. Journal of Engineering Geology,2019,27(1):202-207(in Chinese). [2] ZHANG B, ZHU H, SHAH K W, et al. Performance evaluation and microstructure characterization of seawater and coral/sea sand alkali-activated mortars[J]. Construction and Building Materials,2020,259:120403. doi: 10.1016/j.conbuildmat.2020.120403 [3] 吴杨, 崔杰, 李能, 等. 岛礁吹填珊瑚砂力学行为与颗粒破碎特性试验研究[J]. 岩土力学, 2020, 41(10):3181-3191.WU Yang, CUI Jie, LI Neng, et al. Experimental study on the mechanical behavior and particle breakage characteristics of hydraulic filled coral sand on a coral reef island in the South China Sea[J]. Rock and Soil Mechanics,2020,41(10):3181-3191(in Chinese). [4] CHEN B, CHAO D J, WU W J, et al. Study on creep mechanism of coral sand based on particle breakage evolution law[J]. Journal of Vibro Engineering,2019,21(4):1201-1214. doi: 10.21595/jve.2019.20625 [5] 蔡新光, 赵青, 陈惠苏. 珊瑚混凝土研究现状[J]. 硅酸盐学报, 2021, 49(8):1753-1764.CAI Xinguang, ZHAO Qing, CHEN Huisu. Research progress in coral concrete[J]. Journal of the Chinese Ceramic Society,2021,49(8):1753-1764(in Chinese). [6] 陈宾, 邓坚, 胡杰铭, 等. 钙质砂一维蠕变分形破碎特性宏微观试验研究[J]. 岩土力学, 2022, 43(7):1781-1790.CHEN Bin, DENG Jian, HU Jieming, et al. Macroscopic and microscopic experimental study on fractal fragmentation characteristics of calcareous sand during one-dimensional compression creep[J]. Rock and Soil Mechanics,2022,43(7):1781-1790(in Chinese). [7] 程志海, 杨森, 袁小亚. 石墨烯及其衍生物掺配水泥基材料研究进展[J]. 复合材料学报, 2021, 38(2):339-360.CHENG Zhihai, YANG Sen, YUAN Xiaoya. Research progress of cement-based materials blended with graphene and its derivatives[J]. Acta Materiae Compositae Sinica,2021,38(2):339-360(in Chinese). [8] 彭晖, 戈娅萍, 杨振天, 等. 氧化石墨烯增强水泥基复合材料的力学性能及微观结构[J]. 复合材料学报, 2018, 35(8):2132-2139.PENG Hui, GE Yaping, YANG Zhentian, et al. Mechanical properties and microstructure of graphene oxide reinforced cement-based composites[J]. Acta Materiae Compositae Sinica,2018,35(8):2132-2139(in Chinese). [9] WANG Y H, YANG J W, DONG O Y. Effect of graphene oxide on mechanical properties of cement mortar and its strengthening mechanism[J]. Materials,2019,12(22):3753. doi: 10.3390/ma12223753 [10] YANG F, XIE J, WANG W, et al. Effect of graphene oxide or triethanolamine-modified graphene oxide on the hydration of calcium sulfoaluminate cement[J]. Construction and Building Materials,2022,345:128315. doi: 10.1016/j.conbuildmat.2022.128315 [11] XU Z F, DAI T, GUI C, et al. Study on properties of graphene oxide modified recycled cement-based compo-sites[J]. Integrated Ferroelectrics,2022,227(1):132-144. doi: 10.1080/10584587.2022.2065580 [12] LEE S J, JEONG S H, KIM D U, et al. Graphene oxide as an additive to enhance the strength of cementitious compo-sites[J]. Composite Structures,2020,242:112154. doi: 10.1016/j.compstruct.2020.112154 [13] 吴家文, 马林建, 孔新立, 等. 冲击荷载下全珊瑚混凝土动力特性[J]. 建筑材料学报, 2020, 23(3):581-588.WU Jiawen, MA Linjian, KONG Xinli, et al. Dynamic characteristics of coral concrete under impact load[J]. Journal of Building Materials,2020,23(3):581-588(in Chinese). [14] 吴文娟, 汪稔, 朱长歧, 等. 珊瑚骨料混凝土动态压缩性能的试验研究[J]. 建筑材料学报, 2019, 22(1):7-14. doi: 10.3969/j.issn.1007-9629.2019.01.002WU Wenjuan, WANG Ren, ZHU Changqi, et al. Experimental study on dynamic compression performance of coral aggregate concrete[J]. Journal of Building Materials,2019,22(1):7-14(in Chinese). doi: 10.3969/j.issn.1007-9629.2019.01.002 [15] 吴彰钰, 余红发, 麻海燕, 等. C45珊瑚混凝土的冲击压缩性能试验及数值模拟[J]. 东南大学学报(自然科学版), 2020, 50(3):488-495.WU Zhangyu, YU Hongfa, MA Haiyan, et al. Experiment and numerical simulation on impact compressive properties of C45 coral aggregate concrete[J]. Journal of Southeast University (Natural Science Edition),2020,50(3):488-495(in Chinese). [16] CHEN B, ZHANG J, ZHAO Y, et al. Experimental study on mechanism of graphene oxide-modified coral sand cement mortar to resist sulfate erosion[J]. Geofluids,2022,2022:1905439. [17] CHEN B, HE Y, ZHANG Z, et al. Effects of graphene oxide on chloride ion penetration and microstructure of coral-sand cement stones[J]. Marine Georesources & Geotechnology,2022,41(7):743-750. [18] WANG L, MEI J, WU J, et al. Mechanical properties and microscopic mechanism of coral sand-cement mortar[J]. Advances in Materials Science and Engineering,2020,2020:4854892. [19] QIN Y, XU D, ZHANG S, et al. Dynamic behavior of carbon nanotubes and basalt fiber reinforced coral sand cement mortar at high strain rates[J]. Construction and Building Materials,2022,340:127396. doi: 10.1016/j.conbuildmat.2022.127396 [20] 中国建筑材料科学研究总院. 水泥胶砂强度检验方法(ISO法): GB/T 17671—2021[S]. 北京: 中国标准出版社, 2021.China Building Materials Academy. Test method for cement mortar strength (ISO method): GB/T 17671—2021[S]. Beijing: Standards Press of China, 2021(in Chinese). [21] 高光发, 郭扬波. 高强混凝土动态压缩试验分析[J]. 爆炸与冲击, 2019, 39(3):63-72.GAO Guangfa, GUO Yangbo. Analysis of the dynamic compressive test of high strength concrete[J]. Explosion and Shock Waves,2019,39(3):63-72(in Chinese). [22] 王礼立, 王永刚. 应力波在用 SHPB 研究材料动态本构特性中的重要作用[J]. 爆炸与冲击, 2005, 25(1):17-25. doi: 10.3321/j.issn:1001-1455.2005.01.004WANG Lili, WANG Yonggang. The important role of stress waves in the study on dynamic constitutive behavior of materials by SHPB[J]. Explosion and Shock Waves,2005,25(1):17-25(in Chinese). doi: 10.3321/j.issn:1001-1455.2005.01.004 [23] 宋力, 胡时胜. SHPB 数据处理中的二波法与三波法[J]. 爆炸与冲击, 2005, 25(4):368-373. doi: 10.3321/j.issn:1001-1455.2005.04.014SONG Li, HU Shisheng. Two-wave and three-wave method in SHPB data processing[J]. Explosion and Shock Waves,2005,25(4):368-373(in Chinese). doi: 10.3321/j.issn:1001-1455.2005.04.014 [24] GUO R Q, REN H Q, ZHANG L, et al. Research of an SHPB device in two-by-two form for impact experiments of concrete-like heterogeneous materials[J]. Acta Mechanica Solida Sinica,2021,34(4):561-581. doi: 10.1007/s10338-021-00218-y [25] 刘婷, 麻海燕, 吴彰钰, 等. 碱式硫酸镁水泥混凝土的冲击压缩性能[J]. 建筑材料学报, 2021, 24(3):562-570.LIU Ting, MA Haiyan, WU Zhangyu, et al. Impact compres-sive properties of basic magnesium sulfate cement concrete[J]. Journal of Building Materials,2021,24(3):562-570(in Chinese). [26] HUANG Y J, WANG X F, SHENG M, et al. Dynamic behavior of microcapsule-based self-healing concrete subjected to impact loading[J]. Construction and Building Materials,2021,301:124322. doi: 10.1016/j.conbuildmat.2021.124322 [27] 郑志豪, 任辉启, 龙志林, 等. PP/CF增强珊瑚砂水泥基复合材料冲击压缩力学性能研究[J]. 爆炸与冲击, 2022, 42(7):61-73. doi: 10.11883/bzycj-2021-0297ZHENG Zhihao, REN Huiqi, LONG Zhilin, et al. A study on impact compression mechanical properties of PP/CF reinforced coral sand cement-based composites[J]. Explosion and Shock Waves,2022,42(7):61-73(in Chinese). doi: 10.11883/bzycj-2021-0297 [28] 黄政宇, 王若丁. 应用SHPB试验对超高性能重混凝土动态性能的研究[J]. 铁道科学与工程学报, 2020, 17(11):2798-2806.HUANG Zhengyu, WANG Ruoding. Dynamic behavior of ultra-high performance heavy concrete in split hopkinson pressure bar testing[J]. Journal of Railway Science and Engineering,2020,17(11):2798-2806(in Chinese). [29] SANCHEZ F, ZHANG L. Molecular dynamics modeling of the interface between surface functionalized graphitic structures and calcium-silicate-hydrate: Interaction energies, structure, and dynamics[J]. Journal of Colloid and Interface Science,2008,323(2):349-358. doi: 10.1016/j.jcis.2008.04.023 [30] ZHU P, LI H, LING Q, et al. Mechanical properties and microstructure of a graphene oxide-cement composite[J]. Cement and Concrete Composites,2015,58:140-147. doi: 10.1016/j.cemconcomp.2015.02.001 [31] 吕生华, 张佳, 罗潇倩, 等. 氧化石墨烯/水泥基复合材料的微观结构和性能[J]. 材料研究学报, 2018, 32(3):233-240.LYU Shenghua, ZHANG Jia, LUO Xiaoqian, et al. Microstructure and properties for composites of graphene oxide/cement[J]. Chinese Journal of Materials Research,2018,32(3):233-240(in Chinese). [32] 齐孟, 蒲云东, 杨森, 等. 氧化石墨烯对水泥基渗透结晶型防水材料抗渗性能的影响[J]. 复合材料学报, 2023, 40(3):1598-1610. doi: 10.13801/j.cnki.fhclxb.20220509.003QI Meng, PU Yundong, YANG Sen, et al. Effect of graphene oxide on the impermeability of cementitious capillary crystalline waterproofing[J]. Acta Materiae Compositae Sinica,2023,40(3):1598-1610(in Chinese). doi: 10.13801/j.cnki.fhclxb.20220509.003 [33] QURESHI T S, PANESAR D K, SIDHUREDDY B, et al. Nano-cement composite with graphene oxide produced from epigenetic graphite deposit[J]. Composites Part B: Engineering,2019,159:248-258. doi: 10.1016/j.compositesb.2018.09.095 [34] LYU S H, MA Y J, QIU C C, et al. Effect of graphene oxide nanosheets of microstructure and mechanical properties of cement composites[J]. Construction and Building Materials,2013,49:121-127. doi: 10.1016/j.conbuildmat.2013.08.022 [35] ZENG H Y, QU S, QIN Y H. Microstructure and transport properties of cement-based material enhanced by graphene oxide[J]. Magazine of Concrete Research,2021,73(19):1011-1024. doi: 10.1680/jmacr.19.00558 [36] BIRENBOIM M, NADIV R, ALATAWNA A, et al. Reinforcement and workability aspects of graphene-oxide-reinforced cement nanocomposites[J]. Composites Part B: Engineering,2019,161:68-76. doi: 10.1016/j.compositesb.2018.10.030 [37] WANG Q, WANG J, LU C, et al. Influence of graphene oxide additions on the microstructure and mechanical strength of cement[J]. New Carbon Materials,2015,30(4):349-356. doi: 10.1016/S1872-5805(15)60194-9 [38] LI G, YUAN J B, ZHANG Y H, et al. Microstructure and mechanical performance of graphene reinforced cementitious composites[J]. Composites Part A: Applied Science and Manufacturing,2018,114:188-195. doi: 10.1016/j.compositesa.2018.08.026 [39] 沈文峰, 王亮, 徐颖, 等. 冲击荷载下聚丙烯纤维水泥砂浆力学特性研究[J]. 煤炭科学技术, 2022, 50(8):68-74.SHEN Wenfeng, WANG Liang, XU Ying, et al. Study on mechanical properties of polypropylene fiber cement mortar under impact load[J]. Coal Science and Technology,2022,50(8):68-74(in Chinese). [40] BAI Y L, YAN Z W, JIA J F, et al. Dynamic compressive behavior of concrete confined with unidirectional natural flax FRP based on SHPB tests[J]. Composite Structures,2021,259:113233. doi: 10.1016/j.compstruct.2020.113233 [41] PHAM T M, LIU J, TRAN P, et al. Dynamic compressive properties of lightweight rubberized geopolymer concrete[J]. Construction and Building Materials,2020,265:120753. doi: 10.1016/j.conbuildmat.2020.120753 -
下载:
点击查看大图
图(9) / 表(5)
计量
- 文章访问数: 428
- HTML全文浏览量: 247
- PDF下载量: 30
- 被引次数: 0
