粉煤灰-水泥浆体的流变性能

Rheological Properties of Cement Pastes with Fly Ash

采用回转型粘度计测定了粉煤灰水泥浆体的流变参数 ,并探讨了粉煤灰品种、掺量、颗粒群特征等参数与粉煤灰 水泥浆体流变性能的关系 .结果表明 :新拌水泥浆体的流变性属于宾汉姆体 ,粉煤灰的掺入并未改变其流变特性 ;粉煤灰的圆度和体积比表面积影响着粉煤灰水泥浆体的屈服应力、塑性粘度和触变性的大小 ;粉煤灰 水泥浆体的触变性表现为剪切稀化 ,拆散常数B和破坏面积A这 2个参数均可用作水泥浆体触变性的定量表征 .

By using the rotation viscometer, the rheological properties of fresh cement pastes with fly ash were tested. Also, the relationships between fly ash dosage, the characteristic of particle group of fly ash and the theology of cement pastes with fly ash were discussed. The test results showed that rheological behaviour of fresh cement pastes follows Bingham model and mixing fly ash does not change its rheological property. The roundness and specific surface area of fly ash can affect yield stress, plastic viscosity and thixotropy. The thixotropy of cement pastes with fly ash follows stress thinning behaviour. Both breakdown constant B and destruction area A can show quantitatively cement paste's thixotropy.