Assessment of long term durability properties of blended fly ash-Rice husk ash alkali activated concrete

被引：18

作者：

Fernando, Sarah ^{[1
,2
]}

Gunasekara, Chamila ^{[1
]}

Law, David W. ^{[1
]}

Nasvi, M. C. M. ^{[2
]}

Setunge, Sujeeva ^{[1
]}

Dissanayake, Ranjith ^{[2
]}

机构：

[1] RMIT Univ, Sch Engn, Melbourne, Vic 3000, Australia

[2] Univ Peradeniya, Fac Engn, Peradeniya, Sri Lanka

来源：

CONSTRUCTION AND BUILDING MATERIALS | 2023年 / 369卷

基金：

澳大利亚研究理事会;

关键词：

Alkali activated concrete; Fly ash; Rice husk ash; Durability; Pore structure; Permeation properties; GEOPOLYMER CONCRETE; MECHANICAL-PROPERTIES; CHLORIDE PERMEABILITY; NANO-SILICA; CARBONATION; SLAG; PERFORMANCE; CEMENT;

D O I：

10.1016/j.conbuildmat.2023.130449

中图分类号：

TU [建筑科学];

学科分类号：

0813 ;

摘要：

This study evaluates the long term (up to 365 days) durability properties (i.e., absorption and permeability properties) of a blended fly ash-rice husk ash (RHA) AAC and compares the results with 100 % fly ash AAC. The results showed that the addition of RHA adversely affected the durability characteristics. Degradation of the alkali-activated binder through long-term crack propagation (initiated during heat curing) due to the formation of efflorescence products is identified as one of the major factors contributing to the deterioration observed. The combined effect of the degree of crack propagation and the homogeneity within the microstructure are the main factors that influence the long-term durability properties of blended fly ash-RHA AAC. However, the blended fly ash-RHA AAC had a lower chloride diffusion coefficient at both 28 and 365 days and a higher maturity factor than 100 % fly ash AAC, indicating improved resistance to chloride ingress over time. Overall, the crack propagation becomes the dominant mechanism over the longer term (365 days) despite initial ongoing alkali activation.

引用

页数：13

共 55 条

[1] Durability evaluation of geopolymer and conventional concretes [J].