The role of water-treated municipal solid waste incineration (MSWI) bottom ash in microstructure formation and strength development of blended cement pastes

This research explored the microstructure formation and strength development of blended cement pastes prepared with municipal solid waste incineration (MSWI) bottom ash. A new sample preparation approach involving water treatment of MSWI bottom ash was developed to prevent sample cracking caused by the presence of metallic aluminum (Al) in...

Self-healing of cementitious materials using sustainable cenosphere-based manufactured aggregate

Self-healing concrete using encapsulated healing agent has shown great potential in enhancing concrete durability. However, the capsules are expensive to make and can lower the mechanical properties of concrete. In this study, a new type of manufactured aggregate that employs waste-derived fly ash cenosphere as a carrier of healing agent (SH...

Fresh properties of limestone-calcined clay-slag cement pastes

Formulation of quaternary blended system containing ordinary Portland cement or clinker, slag, limestone and calcined clay (LC2) appeared to be a viable approach to developing low-clinker cements without severely sacrificing mechanical performance at later ages. This paper investigates the effect of two material parameters, i.e., LC2-to-slag...

The quest for a better solvent for the direct hydration of cyclohexene: From molecular screening to process design

Cylcohexanol is an essential bulk chemical that can be produced via cyclohexene hydration, a liquid-liquid two-phase reaction that is limited by the low reaction rate and the equilibrium conversion. Adding an appropriate solvent is the most promising method to break through these limitations. However, in previous works the solvent was almost...

A continuum model for carbonation curing of fibre-cement composites

Accelerated carbonation curing of cellulose fiber-cement composites is known to improve their durability in the form of decreased porosity and increased mechanical properties. In addition, because carbonation results in a decrease in the alkalinity of cement paste, it makes cement less aggressive towards the cellulose fibers. The properties of...

The influence of hydration on the microstructure development of cement paste with bleeding: An NMR study

Bleeding can be described as water coming out from fresh cement paste, which not only affects the homogeneity at fresh stage but also decides the hardened state structure. Previous studies have focused on the determination or simulation of the bleeding extent of fresh cement paste and give objective conclusions. However, there are rare...

Effect of sulfates on hydration and properties of belite-rich cement paste

It is common practice to use gypsum in cement production to control setting time. Traditionally it is believed that sulfate from gypsum combines with aluminates to form ettringite and monosulfate to prevent flash set. However, previous studies have confirmed that sulfates also affect the hydration and mechanical properties of pure alite paste....

Fe incorporation in cement hydrates: experiments and thermodynamic modeling

Current understanding of the state of Fe during the hydration of cement is very limited and further studies are necessary to find out the possible incorporation of Fe in cement hydrates. Moreover, it is important to understand the hydration reaction and properties development of ferrite-rich cement. Our previous study [1] reported the hydration...

Surface characterization of carbonated recycled concrete fines and its effect on the rheology, hydration and strength development of cement paste

Carbonation treatment can effectively improve the performance of recycled concrete aggregate and fines due to the reactions of CO₂ with CH and C–S–H gel of cement paste. To better understand the mechanisms involved in the performance improvement, the surface properties of carbonated recycled cement paste powder (CRP) and its effect...

Simulation of moisture transport in hydrating cement-based overlay systems

Drying of cement-based overlay systems is a critical issue, because it causes differential shrinkage between the overlay material and the concrete substrate and may induce cracking or debonding of the overlay material. In this paper the mechanisms of moisture transport in hydrating cement-based overlay systems are studied. A model is proposed...

Extension of the Hymostruc3D model for simulation of hydration and microstructure development of blended cements

The HYMOSTRUC3D model has been used successfully to predict hydration and microstructure development of pure Portland cement paste. In recent years, a number of numerical models were proposed for optimizing the use of supplementary cementitious materials. Also HYMOSTRUC3D was extended for simulating the hydration and microstructure development...

Quantification of changes in skin hydration and sebum after tape stripping using infrared spectroscopy

Skin barrier function relies on well balanced water and lipid system of stratum corneum. Optimal hydration and oiliness levels are indicators of skin health and integrity. We demonstrate an accurate and sensitive depth profiling of stratum corneum sebum and hydration levels using short wave infrared spectroscopy in the spectral range around...

Numerical simulation of the hydration process and the development of microstructure of self-compacting cement paste containing limestone as filler