Characterizing two types of zonation within slag rims of aged alkali-activated slag pastes through SEM and TEM

In this paper, the authors characterized two types of zonation within slag rims in aged alkali-activated slag (AAS) systems through SEM and TEM technology. These two elemental zonation were closely related to the pore structure of AAS pastes, thus providing strong implication for the transport- and durability-related performance of AAS...

The effect of blast furnace slag chemistry on carbonation characteristics of cement-slag systems

In order to compensate the limited availability of raw material resources and meet the growing demand for decreasing CO2 emissions during cement and concrete productions, a practical method is to decrease the clinker content in cement. This strategy mainly consists of substituting a part of the clinker with supplementary cementitious materials ...

Effect of MgO content on the quantitative role of hydrotalcite-like phase in a cement-slag system during carbonation

This paper reports the carbonation characteristics of a cement-slag system exposed to accelerated carbonation testing, and its improved carbonation resistance with the increasing MgO content in blast furnace slag, in which hydrotalcite-like phase plays a key role. Our research showed that the hydrotalcite-like phase started to carbonate upon...

Elucidating the effect of accelerated carbonation on porosity and mechanical properties of hydrated Portland cement paste using X-ray tomography and advanced micromechanical testing

Carbonation of hydrated cement paste (HCP) causes numerous chemo-mechanical changes in the microstructure, e.g., porosity, strength, elastic modulus, and permeability, which have a significant influence on the durability of concrete structures. Due to its complexity, much is still not understood about the process of carbonation of HCP. The...