石墨烯分散液对再生混凝土工作性能与抗压性能影响研究  

Study on the influence of graphene dispersion on the workability and compressive properties of recycled concrete

作　　者：谢建和 何建华[2] 冯源 麦伟康 XIE Jianhe;HE Jianhua;FENG Yuan;MAI Weikang(School of Construction Engineering,Guangzhou Institute of Science and Technology,Guangzhou 510540,China;School of Civil and Transportation Engineering,Guangdong University of Technology,Guangzhou 510006,China)

机构地区：[1]广州理工学院建筑工程学院,广东广州510540 [2]广东工业大学土木与交通工程学院,广东广州510006

出　　处：《混凝土》2022年第5期98-102,107,共6页Concrete

基　　金：国家自然科学基金(12072078);广东省自然科学基金(2019B151502004);广东省科技计划项目(2017B020238006)。

摘　　要：石墨烯具有优异的物理性能,在混凝土中适当使用可一定程度改善其力学性能和耐久性能,是增强混凝土基体的热门材料。通过物理剪切法制备水基的石墨烯分散液,探讨不同剪切时间的分散液对普通混凝土及再生粗骨料混凝土工作性能和抗压性能的影响。研究结果表明:利用物理剪切法可规模化制备水基石墨烯分散液;水基石墨烯分散液的掺入对混凝土的破坏模式影响较小,但会明显降低拌合物的流动性;该类石墨烯分散液可有效改善混凝土的微观结构,提高普通混凝土的抗压性能;然而,再生骨料的高吸水率和分散液中石墨烯的絮凝作用可能会使再生混凝土的实际水胶比过低,导致石墨烯分散液的掺入起负面作用。因此,利用水基石墨烯分散液改性再生混凝土时,建议控制其实际水胶比,不宜采用石墨烯分散液改性低水胶比的再生混凝土。Graphene has excellent physical properties,which can effectively improve the mechanical properties and durability of concrete to a certain extent as it is used properly.Therefore,graphene is a popular material for strengthening concrete matrix.In this study,water-based graphene dispersion was prepared by physically shear method to investigate the effects of different shear times on the workability and compressive properties of ordinary concrete and recycled coarse aggregate concrete.The results show that this shear method can be used to achieve large-scale production of water-based graphene dispersion.The addition of water-based graphene dispersion has little effect on the failure mode of concrete,but can significantly reduce the fluidity of the mixture.This kind of graphene dispersion can effectively improve the microstructure of concrete and improve the compressive performance of ordinary concrete.However,the high water absorption of recycled aggregate and the flocculation of graphene in the dispersion may significantly reduce the actual water-binder ratio of recycled concrete,resulting in the negative effect of the addition of graphene dispersion.Therefore,it is suggested that the actual water-binder ratio should be controlled when the recycled concrete is modified by water-based graphene dispersion,and it is not appropriate to use graphene dispersion to modify recycled concrete with a low water-binder ratio.

关 键 词：石墨烯分散液 物理剪切法 再生混凝土 流动性 抗压性能 

分 类 号：TU528.042[建筑科学—建筑技术科学]