Influence of Pore Structure on Transport Properties of AASF Mortar under Carbonation Curing

doi:10.16552/j.cnki.issn1001-1625.2025.0348

Abstract

Abstract: Alkali-activated materials, as a novel low-carbon and eco-friendly cementitious material, has attracted significant attention. However, the quantitative relationship between its pore structure and transport properties, which is closely related to durability, remains unclear. To clarify the influence mechanism of pore structure variations on the transport properties of alkali-activated materials, this study employed high-humidity carbonation curing to regulate the microstructure. The effect of carbonation curing on the mechanical properties, pore structure, and transport properties (gas permeability and surface capillary water absorption rate) of alkali-activated slag-fly ash (AASF) mortar was explored. Results demonstrate that carbonation curing changes the distribution of microscopic pore structure. The filling of carbonation products lead to a more uniform pore distribution in both small-pore region (<100 nm) and transitional-pore region (100~10 000 nm), significantly decreasing material transport properties. Gas permeability exhibits a multiplicative reduction, and the capillary water absorption rate even decreases by 66.66% for the sample with 40% (mass fraction) fly ash, thereby contributing to enhanced durability of AASF mortar.

Key words: alkali-activated material, pore structure, transport property, gas permeability, capillary water absorption rate, durability

CLC Number:

TU525

ZHENG Dapeng, YANG Jianxiang, ZHAO Debo, CUI Hongzhi. Influence of Pore Structure on Transport Properties of AASF Mortar under Carbonation Curing[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2025, 44(10): 3713-3724.

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