掺粉煤灰PVA纤维增强水泥基复合材料的试验研究

Experimental Study on High-Ductile PVA Fiber-Reinforced Cement-Based Composite Materials with Fly Ash

研究了粉煤灰掺量对PVA纤维增强水泥基复合材料(ECC)的新拌性能、弯曲性能、抗压抗折强度、开裂模式及微观结构的影响.结果表明:随着粉煤灰掺量的增加,水泥净浆的屈服剪切应力和塑性黏度不断降低,ECC的流动度增加.ECC的初始开裂荷载降低、抗折和抗压强度逐渐降低,ECC的跨中挠度提高,ECC的平均裂缝宽度变小.在满足抗压强度的前提下,适当增加粉煤灰掺量有助于提高ECC的韧性和延性.

The effects of content of fly ash on the fresh properties, the bending properties, compressive strength, flexural strength and cracking pattern of Engineered Cementitious Composites （ECC） are investigated in this paper. The results show that with the increase of fly ash content, the yield stress and viscosity of cement paste decrease, the fluidity of fresh ECC increase. With the increase of fly ash content, the initial cracking load of ECC decreases the flexural and compressive strength gradually decrease, the deflection of ECC enhanced, as well as the average crack width become. If the drop of compressive strength of ECC is permit, increasing fly ash content appropriately will help to further improve the toughness and ductility of ECC.