Mechanical Properties of Engineered Cementitious Composites with High Volume Fly Ash

• 作 者: 祝瑜 杨英姿
• 机 构: School of Material Science and Engineering,Harbin Institute of Technology,School of Civil Engineerin
• 出 处: Journal of Wuhan University of Technology(Materials Science
• 发表日期: 2009年S1期
• 关键词: compressive flexural saturated bonding ductility deflection bending adding tough

In order to improve the mechanical properties and Greenness of engineered cementitious composites (ECC),four-point bending test,compressive strength and flexural strength test were employed to analyze the effects of fly ash content on the mechanical properties of.ECC.The replacement ratio of cement with fly ash was 50%,60%,70% and 80%,respectively.The experimental results indicate that ECCs with high volume fly ash still remained the characteristic of pseudo-strain hardening and the mid-span deflection in four-point bending test increase remarkably by adding more fly ash.The observations of ECCs indicate that the multiple cracks are saturated and the crack width is relatively smaller for higher volume fly ash ECC,owing to the lower strength of matrix and the improvement ofinterface bonding.Fly ash reduces the compressive strength and flexural strength of ECC at all ages.Therefore,as the compressive strength could meet the requirement of practical engineering,employing the higher volume fly ash ECCs would benefit to obtain relatively high ductility.

In order to improve the mechanical properties and greenness of engineered cementitious composites (ECC), four-point bending test, compressive strength and flexural strength test were employed to analyze the effects of fly ash content on the mechanical properties of .ECC.The replacement ratio of cement with fly ash was 50%, 60%, 70% and 80% respectively. The experimental results indicate that ECCs with high volume fly ash still remained the characteristic of pseudo-strain hardening and the mid-span deflection in four-point bending test increase remarkably by adding more fly ash. The observations of ECCs that that multiple cracks are saturated and the crack width is relatively smaller for higher volume fly ash ECC, due to the lower strength of matrix and the improvement of interface bonding. Fly ash reduces the compressive strength and flexural strength of ECC at all ages.Therefore, as the compressive strength could could meet the requirement of practical engineering, employing the higher volume fly ash ECCs would benefit to obtain relatively high ductility.