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采用流变仪和激光共聚焦显微镜对不同氧化石墨烯( GO)掺量的新拌水泥浆体的流变参数以及浆体微观形态进行了定量化研究,并采用Modified-Bingham ( M-B)模型和Herschel-Bulkley ( H-B)模型对所测数据进行了拟合处理,提出了GO影响新拌水泥浆体的作用机理。结果表明,GO的掺入可以使新拌浆体中在减水剂作用下分散的水泥颗粒发生再次凝聚,形成重组絮凝结构,且随着GO掺量的增加,重组絮凝结构的数量越多,从而使得浆体流变性发生显著变化。一方面,新拌浆体的塑性粘度、屈服应力以及触变性随GO掺量的提高而显著增加。另一方面,GO的掺入提高了新拌浆体的临界剪切速率,使其在较大剪切速率下的流变行为仍然表现为剪切变稀；降低了浆体的剪切增稠程度,提高了浆体的稳定性。“,”The rheological properties and morphology of fresh cement pastes with different contents of graphene oxide ( GO) were investigated by a rheometer and a laser confocal scanning microscope, respectively. The rheological data were fitted by the Modi-fied-Bingham ( M-B) model and Herschel-Bulkley ( H-B) model. A mechanism for the effect of GO on the rheological properties is proposed. Results show that the cement particles are re-agglomerated and new flocculation structures are generated by the addition of GO. The new flocculation structures significantly alter the rheological properties of the pastes. The degree of re-agglomeration and the number of new flocculation structures increase with increasing GO content, leading to a sharp increase in the yield stress, plastic viscosity and the area of the hysteresis loop. GO can effectively reduce the degree of shear-thickening, and increase the critical shear rate and the stability of the pastes.