搅拌过程和流变性对水泥基材料中纤维分布及力学性能影响

Effect of Mixing Procedures and Rheology on Fiber Distribution and Mechanical Property of Cementitious Composite (ECC)

纤维增强水泥基设计复合材料(ECC)具有高延性特征,而成型过程影响纤维在水泥基体内分布状态,进而影响ECC获得高延性性能的稳定性。本文综述了ECC搅拌过程和拌合状态下的流变性能对纤维分布的影响,重点分析了塑性黏度和屈服应力对纤维分布及力学性能的影响。结果表明:后加纤维的搅拌过程是ECC成型过程中纤维分布的最优方式;良好的塑性黏度是保证纤维均匀分布的关键,屈服应力影响纤维分布及取向分布;综合调整ECC的流变性可以保证纤维均匀分布,使硬化后ECC获得稳定的高延性。

Engineered cementitious composite（ ECC） is characterized by high ductility. The processing of fresh ECC plays a key role on fiber distribution and then influences robustness of high ductility of hardened ECC. The effects of fresh ECC mixing procedures and rheological property on fiber distribution were summarized,moreover,the effects of plastic viscosity and yield stress of fresh ECC on ECC fiber distribution and mechanical property were significantly studied. The results show that the fresh ECC mixing procedure with adding fibers finally is the optimal way; good plastic viscosity of fresh ECC leads to fiber uniform distribution,and yield stress is related to fiber distribution and fiber orientation distribution;Good fiber distribution is obtained by adjusting the rheological property,which results in acquiring robust high ductility of hardened ECC.