Characterization, pre-treatment, and potential applications of fine MSWI bottom ash as a supplementary cementitious material

With the development of waste recovery techniques, previous research has revealed that coarse fractions of municipal solid waste incineration (MSWI) bottom ash (BA) after proper treatment could be applied in the construction sector, while the fines are seldom recovered in practice and normally landfilled. This study explores the potential...

Geopolymeerbeton voor infrastructurele toepassingen (1): Ontwikkeling van zelfverdichtende mengsels

In Nederland wordt veel aandacht besteed aan geopolymeerbeton als een van de mogelijkheden om de CO₂-voetafdruk van beton te verlagen. Hoewel dit materiaal op laboratoriumschaal uitgebreid is onderzocht, zijn praktische toepassingen en ervaringen nog maar beperkt beschikbaar. Bovendien bestaan er voor een brede en grootschalige constructieve...

Time-dependent material properties and reinforced beams behavior of two alkali-activated types of concrete

This paper presents an experimental study on the development of material properties over time (up to around 2 years) and the structural behavior of reinforced beams, for two types of alkali-activated concrete (AAC). Compressive strength, flexural strength, tensile splitting strength, elastic modulus, and flexural behavior of reinforced beams...

Geocon bridge geopolymer concrete mixture for structural applications

The sustainability of infrastructure projects is becoming increasingly important issue in engineering practice. This means that in the future the construction materials will be selected on the basis of the contribution they can make to reach sustainability requirements. Geopolymers are materials based on by-products from industries. By using...

Development and application of an environmentally friendly ductile alkali-activated composite

This paper presents a development of a ductile alkali-activated fly ash (FA) and ground granulated blast furnace slag (GBFS) based composite as an environmentally friendly material for structural concrete application. For this purpose, polyvinyl alcohol (PVA) fibres and sand aggregate were combined with alkali-activated paste. Workability,...

Effect of natural carbonation on the pore structure and elastic modulus of the alkali-activated fly ash and slag pastes

The aim of this paper was to investigate the effect of natural carbonation on the pore structure, and elastic modulus (E_m) of alkali-activated fly ash (FA) and ground granulated blast furnace slag (GBFS) pastes after one year of exposure in the natural laboratory conditions. The chemical changes due to carbonation were examined by...

Moisture movement in cement-based repair systems monitored by X-ray absorption

In concrete repair systems, material properties in the repair material and interface are greatly influenced by the initial moisture content of the concrete (or mortar) substrate. In order to quantify moisture profiles inside the repair system, X-ray absorption was used. Preliminary studies are performed first to determine the absorption rate of...

Failure Modes in Concrete Repair Systems due to Ongoing Corrosion

Corrosion of steel reinforcement is the main cause of deterioration in reinforced concrete structures. It can result in cracking and spalling of the concrete cover. After the damaged cover is repaired, reinforcement corrosion might continue and even accelerate. While the development of the corrosion cell is difficult to control, the damage can...

Elastic modulus of the alkali-silica reaction rim in a simplified calcium-alkali-silicate system determined by nano-indentation

This work aims at providing a better understanding of the mechanical properties of the reaction rim in the alkali-silica reaction. The elastic modulus of the calcium alkali silicate constituting the reaction rim, which is formed at the interface between alkali silicate and Ca(OH)2 in a chemically-idealized system of the alkali-silica reaction...

A 3D Lattice Modelling Study of Drying Shrinkage Damage in Concrete Repair Systems

Differential shrinkage between repair material and concrete substrate is considered to be the main cause of premature failure of repair systems. The magnitude of induced stresses depends on many factors, for example the degree of restraint, moisture gradients caused by curing and drying conditions, type of repair material, etc. Numerical...

Effect of Moisture Exchange on Interface Formation in the Repair System Studied by X-ray Absorption

In concrete repair systems, material properties of the repair material and the interface are greatly influenced by the moisture exchange between the repair material and the substrate. If the substrate is dry, it can absorb water from the repair material and reduce its effective water-to-cement ratio (w/c). This further affects the hydration rate...

Micromechanical study of the interface properties in concrete repair systems