Creep of alkali-activated fly ash and slag concrete: Unveiling multiscale dynamics

Climate change is the main global concern today, triggering a transformative shift in several sectors, especially the construction industry. High carbon emissions during Portland cement (PC) production necessitate a gradual shift toward more environmentally friendly alternatives, such as alkali-activated materials (AAMs). AAMs offer a promising,...

Recycling of Aluminosilicate-Based Solid Wastes through Alkali-Activation: Preparation, Characterization, and Challenges

Recycling aluminosilicate-based solid wastes is imperative to realize the sustainable development of constructions. By using alkali activation technology, aluminosilicate-based solid wastes, such as furnace slag, fly ash, red mud, and most of the bio-ashes, can be turned into alternative binder materials to Portland cement to reduce the carbon...

The influence of granite powder waste and the addition of fly ash on concrete bleeding

Bleeding is a common problem in concrete slabs, and may lead to serious damage. The goal of this article is to understand the impact of alternative binders and their properties on the bleeding of concrete. Therefore, the impact of the type of binder on the bleeding process is investigated. The results show that the addition of granite powder...

Improve the long-term property of heat-cured mortars blended with fly ash by internal curing

Due to the satisfactory property and high productivity, heat-cured concretes have been widely used in engineering practice. However, heat curing process also brings some drawbacks that are detrimental to the long-term property of this material. To address this issue, lightweight fine aggregate (LWFA) was employed to provide internal curing ...

Autogenous shrinkage of alkali-activated slag and fly ash materials: From mechanism to mitigating strategies

Alkali-activated materials (AAMs), as eco-friendly alternatives to Ordinary Portland cement (OPC), have attracted increasing attention of researchers in the past decades. Unlike cement, which requires calcination of limestone, AAMs can be made from industrial by-products, or even wastes, with the use of alkali-activator. The production of AAMs...

Lowering iron losses during slag removal in hot metal desulphurisation without using fluoride

To lower the iron losses of the hot metal desulphurisation (HMD) process, slag modifiers can be added to the slag. Slag modifiers decrease the apparent viscosity of the HMD slag. Most common slag modifiers in industry contain fluoride as a fluidiser. However, fluoride leads to a higher magnesium consumption and has health, safety and...

Experimental Study and Numerical Simulation of the Reaction Process and Microstructure Formation of Alkali-Activated Materials

Alkali-activated materials (AAMs) show promising potentials for use as building materials. Before the utilization, AAMs must satisfy the properties required from the construction sector, such as good durability and long-term service life. These properties mainly depend on the chemical and physical properties of the microstructure of AAMs. In the...

Autogenous shrinkage of early age cement paste and mortar

Concrete is a brittle composite material that easily fractures under tension. Due to the fact that the early-age deformation of the concrete member is restrained by adjoining structures, cracking can occur throughout the concrete prior to application of any load. The cracks would provide preferential access for aggressive agents penetrating in...

Simulation of hydration and microstructure development of blended cements

For optimization of the use of Supplementary Cementitious Materials (SCMs), i.e. blast furnace slag (BFS) and fly ash (FA), in cementitious system a numerical model for simulating the hydration and microstructure development of blended cements can be used. Several models have been proposed in recent years to simulate the hydration and...

New phosphate glasses containing industrial waste and their applications for building engineering

Despite a large number of products developed from waste materials, most of them consist of non-transparent applications, partly because it is a challenge to get transparent materials at reasonable temperatures from these waste products. In this work, we produced transparent glass samples incorporating slag and fly ash into a phosphate glass...

Fly ash from coal and biomass for use in concrete: Origin, properties and performance

Coal fly ash is widely used in as raw material in concrete industry because it can replace part of the cement and fly ash contributes to improve certain properties of concrete. As a way to reduce the contribution of coal fired power plants to the climate change, more and more coal is replaced by biomass. To keep fly ash as a valuable resource...

Experimental study on workability of alkali activated fly ash and slag-based geopolymer concretes

This paper presents an investigation on workability and strength of geopolymer concrete made of fly ash (FA), blast furnace slag (BFS) and a multicompound activator of Na2SiO3 and NaOH solutions. The FA/BFS ratios were 100:0, 70:30, 60:40, 50:50, 40:60, 30:70 and 0:100. The workability of geopolymer concretes was performed by using slump test...

Microstructure Development and Transport Properties of Portland Cement-fly Ash Binary Systems: In view of service life predictions

Fly ash is a by-product of burning coal in electric power generating plants. It is commonly known that owing to its pozzolanic properties fly ash is widely used as a partial replacement for Portland cement in concrete. The use of fly ash in concrete not only reduces the landfill costs of fly ash, but also reduces the use of Portland cement in...

Effects of slag and fly ash on reinforcement corrosion in concrete in chloride environment: Research from the Netherlands

A review is given of research on the durability performance of concrete made with blast furnace slag and fly ash related to chloride induced reinforcement corrosion, carried out in the Netherlands, where slag has been used in cement for almost a century. Results are presented from field studies on concrete in marine environment and laboratory...

Application of TEM to characterize fly ash- and slag cements

A Portland fly ash cement containing 20% of a fine fly ash and a blast furnace slag cement of approximately 290 days old were examined with analytical transmission electron microscopy, in order to examine the (local) microstructure in these cements in detail. In the Portland fly ash cement the fly ash reacted with CH resulting from the cement...

Reactivity of Fly Ash and Slag in Cement, Reactiviteit van poederkooivliegas en slak in cement