氧化石墨烯分散液对混凝土抗盐冻性能的影响  

Effects of graphene oxide dispersion on the salt-frost resistance of concrete

作　　者：徐义洪[1,2] 范颖芳 XU Yihong;FAN Yingfang(Institute of Road and Bridge Engineering,Dalian Maritime University,Dalian 116026,China;Liaoning Bridge Safety Engineering Technology Research Center,Shenyang 110122,China)

机构地区：[1]大连海事大学道路与桥梁工程研究所,辽宁大连116026 [2]辽宁省桥梁安全工程技术研究中心,辽宁沈阳110122

出　　处：《混凝土》2022年第2期1-5,共5页Concrete

基　　金：国家自然科学基金资助项目(51578099)。

摘　　要：为研究不同掺量氧化石墨烯分散液对混凝土抗盐冻性能的影响,采用改进Hummers法和超声波分散法制备了浓度为5 m L/mg氧化石墨烯片层分散液,利用FTIR和XRD对GO分散性进行了结构表征;研究了不同GO掺量条件下盐混凝土试件的力学和耐久性能,并借助微观测试手段分析不同GO掺量对盐冻混凝土微结构的影响。试验得出随着盐冻次数的增加,GO混凝土劣化模式表现为砂浆脱落、微裂纹扩展、剥蚀和块状脱落等多种形式相结合;GO的最佳掺量为0.03%,在该掺量下,相比与基准试件,盐冻200次后试件抗压强度提高34.83%,质量和动弹性模量损失率最小;微观测试结果表明:适量的氧化石墨烯能够促进水泥水化进程,调控其微观结构,有效阻碍盐冻循环对混凝土微观形貌的破坏,抑制内部微裂纹的萌生与扩展;从而提高盐冻后试件的力学和耐久性能。In order to study the effect of different dosage of graphene oxide dispersion on the salt-frost resistance of concrete,a graphene oxide dispersion at a concentration of 5 m L/mg was prepared by improving hummers method and ultrasonic dispersion method.The resulting GO dispersion were characterized by FTIR and X-ray photoelectron spectroscopy.The influence of GO additives on the mechanical and durability properties and flexural strength was investigated,and analyzed the the influence of the microstructure of concrete by the microscopic test.It found that the deterioration mode of GO concrete presented a combination of mortar slabbing,micro-crack propagation,denudation and block slabbing.The best dosage of GO is 0.03%,under which,compared to the benchmark sample,the compressive strength increased by 34.83%,the mass loss rate and dynamic elastic modulus reduced minimum after the 200 of salt-frost times.Microscopic test results indicated that the right amount of graphene oxide can promote hydration process of the cement,control the microstructure,effectively prevent the microstructure of concrete from damage,slow internal micro cracks initiation and propagation in order to improve the mechanics and durability of the salt after frozen specimen.

关 键 词：氧化石墨烯 盐冻 抗压强度 SEM 气泡特征 微观结构 

分 类 号：TU528.01[建筑科学—建筑技术科学]