掺氧化石墨烯水泥复合净浆的自收缩机理研究

Autogenous shrinkage mechanism analysis of cement-based composite paste with addition of graphene oxide

氧化石墨烯(GO)基面含有丰富的含氧官能团,同时具有较大的比表面积,可以改变水泥产物的形状及聚集形态、密实水泥基材料的微观结构、进而改善其力学性能。研究了水灰比和GO掺量对氧化石墨烯/水泥复合净浆(GO/C)自收缩特性的影响。结果表明:GO/C的自收缩受水化龄期、水灰比和GO掺量的影响较大,当水灰比为0.42、GO掺量为0.03%时,对水泥净浆自收缩的抑制作用可以达到最优,此时GO/C的28 d自收缩为1.53 mL/100 g,较对照组减小了25%。

Graphene oxide(GO)has rich oxygen-containing functional groups and large specific surface area,which can change the shape and aggregation morphology of cement products,densify the microstructure of cement-based composite materials,and improve their mechanical properties.The effect of water-cement ratio and GO dosing on autogenous shrinkage properties of graphene oxide/cement composite paste(GO/C)was studied.The experimental results show that the autogenous shrinkage of GO/C is greatly influenced by the hydration age,water-cement ratio and GO dosing.The inhibition of the autogenous-shrinkage of cement paste can reach the optimal effect when the water-cement ratio is 0.42 and the GO dosing is 0.03%.At this time,the 28 d self-shrinkage of GO/C is 1.53 mL/100 g,which is 25%smaller compared to the reference group.