Investigations into effective fly ash used in concrete

Abstract

This work presents a study on the influence of thermal-electrical fly ash on the cement paste hydration processes, investigation into cement stone, mortar, ordinary and self-compacting concrete, when cement was replaced by fly ash (533 %). It was estimated that cement stone and cement paste prepared from fly ash and cement properties were better when polycarboxylic superplasticiser Visco Crete-3 was used. It was established that admixture of fly ash influences the processes of cement hydration: the amount of free Ca(OH) 2 in cement stone was decreased and amount of stable calcium hydro silicates was increased. It allows to state, that cement stone becomes more corrosion-resistant and more durable. When fly ash admixture is applied in ordinary concrete production, it is possibility to reduce cement expenditures up to 33 % and in self-compacting concrete production, segregation and separation of water decreases. Data of investigations on hardened concrete showed that fly ash increases compressive strength (up to 15 %), decreases shrinkage strains (up to 31,6 %), increases plastic deformations (up to 38 %), modulus of elasticity (up to 15 %) and modifies other concrete properties.

A Review on Partial Replacement of Cement in Concrete by Three Supplementary Materials

“…In compare to the reference mortar (i.e. mix with 0% fly ash) about 5% and 17% lower density was found for the mortar mixes with 10% and 30% fly ash (Rudzionis and Ivanauskas, 2004). Density of concrete also related to the optimum content of fly ash.…”

“…The density of cement mortar reduced as the percentages of fly ash content increased in the mixes (Rudzionis and Ivanauskas, 2004). In compare to the reference mortar (i.e.…”

Stabilization of Clay Powder With Mineral Wool Fly Ash

“…One of the main problems while working with FA is that their composition is very different and it depends on incinerated materials (Vaitkus et al, 2017;Rudžionis & Ivanauskas, 2004). The properties of FA which were collected even in the same factory but in different times may differ (Rutkauskas, 2018), therefore FA collected during the production of mineral wool gain and advantage due to constant and more predictable composition.…”

Influence of Composite Elastic Modulus and Lateral Load Pattern on Deflection of Anti-Slide Pile Head

“…Sližytė (2001aSližytė ( , 2001b conducted the study on estimation of axially-loaded bored piles interaction in the design of pile foundation, and also examined the interaction estimation of piles bored in sand. Rudžionis and Ivanauskas (2004) presented a study on the influence of thermal-electrical fly ash on the cement paste hydration process. In order to increase the strength of the structural elements under the specific service condition, Bulavs et al (2005) developed a way of improving the capacity in bending by the use of FRP layers on RC beams with taking into account the non-linear deformation character.…”