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Into this paper there are presented physical and mechanical properties of control samples from self-compacting concrete realized with fly ash and silica fume (like powders) and superplasticizer. The slump of fresh self-compacting concrete was 680 mm, L-box h1/h2=0.92 and V-funnel = 12 sec. There were realized prismatic samples with dimensions 10 x 10 x 30 cm. The control samples were kept into laboratory curing conditions. The testing ages were at 28 days and 9 years. At 28 days age, the compressive strengths on p...

The purpose of this research was to study, analyze and evaluate strategies and concepts for recycling of waste related to the rests of burning processes form fossil fuels in the energy sector in transition countries. Accordingly to the European Opinion approach the objectives in future are to reduce the fossil energy resource utilization in order to minimize the negative impacts on the environment and human health. Meanwhile in countries that largely depend in energy production based on thermo power plants the mai...

The objective of this research is to study in laboratory?s materials such as: cationic bituminous emulsions, aggregates, fly ash, etc., in order to develop optimal and appropriate mix formula for "cold" waste asphalt recycling with the addition of slow breaking cationic bituminous emulsions, fly ash, cement and natural aggregates. The purpose of this approach is to obtain an "optimal combination" comprising the above-mentioned materials as well as the mixing of the wear layer on the surface of the road on which th...

In last years, recycling has become a strategic factor in global politics, a vital component and a cost factor for economic development and the progress of society as a whole, generating a number of major global concerns. Exceeding twice the sum of all materials used in construction, annual concrete consumption around the world amounts to approximately 10 trillion tones being by far the most used building material and the partial or total replacement of a component of its mass with recyclable waste has a major pos...

The paper examines the various developments regarding strategic management of raw materials on national, European and international levels. The problems linked to this subject are of increasing importance for the producing industry. Thus it is necessary to act quickly and pursue a sustainable raw material policy. The main purpose of this work is to analyze the possibility of fly ash utilization for the road construction and possible application in other industry branches with interest. The methodology used in the ...

The paper presents the research on the modification lightweight cement composites with organic fillers by fly ash and anionic bitumen emulsion addition. Organic fillers used in composites were: common reed (fraction 2/10 and 10/20 mm) and conifer sawdust (fraction 0/2 mm). The reed Phragmites australis is a notably common plant in Poland that grows on waterlogged lands. This material is renewable, ecological, and while vegetation absorbs carbon dioxide. To determine the influence of two factors on composites? prop...

The publication presents an assessment of the possibility of obtaining char from fly and fluidised ashes from coal combustion. It also presents the methodology of measuring the concentration of char in fly ashes as well as the method developed for separating char grains from fly ash samples. The research conducted has shown that both fly and fluidised ashes contain large quantities of unburnt coal grains, which can be used as a substitute in obtaining artificial graphite through the processes of graphitisation. Th...

The benefit of recycling industrial by-products in the construction industry led to growing interest in exploring and potentially exploiting these by-products, in the context of sustainable development, and in creating new materials. Fly ash is a type of byproduct waste, having enjoyed considerable attention, especially from the perspective of creating and perfecting fly ash based geopolymer concrete. In Romania, over 80% of industrial waste is deposited, this being the most widely used method of waste disposal. T...

According to data reported in the EU report, critical raw materials include 20 raw materials, including rare earth heavy metals (Gd-Lu and Y) and rare earth light metals (La-Eu). Thus, rare earth metals include lanthanides of atomic number 58-71 and scandiums with atomic numbers Sc -21, Y -39 and La -57, respectively. Rare earth metals are used in many modern, innovative techniques such as optics, nuclear technology, production of permanent magnets that are part of discs for computers and automotive hybrid motors,...

This paper presents a study of performance evaluation of some fluid cement-based mortars containing mineral admixtures used as structural bonding material for fixing reinforcing steel bars in hardened concrete. The paper includes the developing of performance anchoring mortar for post-installed rebars based on ordinary blended cements. A series of standardized tests were performed within the experimental setup with the objective of assessing the performance of the mortars in terms of fluidity, cohesiveness and ear...

New building materials were obtained in the last decades by using different types of cements, aggregates, additives or additions. Additions such as s powder, aggregate, fiber, etc. were tested for obtaining new properties of concrete or for finding a way to consume the wastes. The paper presents the experimental results obtained on fly ash concrete with waste fibers. The concrete was prepared with substitution of cement with fly ash in different dosages (10%, 15%, 20%, 30% and 40%) and two types of fibers (hemp an...

The Power Plant Rybnik (Elektrownia Rybnik) is one of many in Poland, which is coal-fired. Fly ash, as is well known, are combustion by-products, which are mineral residue from burning coal. Their phase composition depends mainly on the quality of fuel (coal) and combustion conditions. In the mineral composition of the examined ashes one has identified minerals such as: glaze, quartz, mullite, spinels, hematite, and unburnt coal. Spinels present in the fly ash can be a source of some metals, and due to the magneti...

The Rare Earth Elements (REE) have been classified as resources critical for the European Union and divided into: light rare earth elements and heavy rare earth elements. The demand for REE is constantly increasing, which is connected with the wide range of their applications. The article presents the results of research conducted to determine the concentration of Rare Earth Elements in fly ashes obtained from the combustion of coal at the Rybnik Power Plant. The concentrations were measured using the ICP-MS and S...