Relationship of amorphous gel-microstructure-elastoviscosity properties of alkali-activated materials fresh pastes with different Ms waterglass

摘要

In-situ measurement and quantitative analysis method were applied for the elastoviscosity properties of alkali-activated fly ash-slag with different Ms waterglass in this study. Some critical effect of the microstructure and amorphous gel on the elastoviscosity properties were fully discussed, including mesh size of microstructure, formation and transformation of amorphous gel when using Microrheology analyzer, In-situ ATR FTIR, SEM-EDX, selected dissolution process, and Low-field NMR. Results indicate that the amorphous gel was main reasons on the development of microstructure and elastoviscosity properties of alkali-activated fly ash-slag. Competitive formation mechanism between N-A-S-H gel and C-(A)-S H gel was the main reasons of rheology properties of alkali activated materials fresh pastes: high N-A-S-H gel content of particle surfaces improve the touch point of particles-particles, increasing the formation trendy of the small mesh size and resulting to the lower rheology index. But, the formation of C-(A)-S H gel results to the decreasing of free water due to the high interlayer space and product water. It would lead to the increasing of pore structure and mesh size.(c) 2021 Elsevier Ltd. All rights reserved.