Rapport scientifique et technique final - Partenaire ULiège-GeMMe

Dans ce rapport final, nous avons choisi de présenter les résultats en fonction des produits testés (et non des tâches). Les travaux de recherche présentés dans ce rapport sont exposés en trois chapitres : 1. le premier chapitre traite des cendres volantes de charbon et des cendres volantes de biomasse ; 2. le deuxième chapitre décrit les travaux de recherche réalisés sur les granulats recyclés de béton, notamment en combinaison avec des fillers calcaires pour la formulation de bétons ; 3. le troisième chapitre porte sur la caractérisation des granulats recyclés de mâchefers d’incinérateur d’ordures ménagères (MIOM) et sur la formulation de bétons

Geopolymer composites based on fly Ash from co-combustion of coal and biomass

Geopolymers have been the subject of substantial research and commercial interest during the beginning of this century. Through the alkali-activation process, by-products obtained from coal or co-combustion can be used as a valuable product. Regrettably, the variability of the chemical composition of the source materials results in fluctuation of performance levels of the alkali-activated materials (AAMs). Research has been until now focused on the factors influencing geopolymerization process, mechanical properties and durability: geopolymer composites have definitively excellent engineering properties as a building material. However, these high durability performances are greatly depending on different geopolymerization precursors, activators, types of specimens and research methodology. The subject of this PhD research is the study of AAMs produced with new combustion by-products (biomass and co-fired fly ashes) and their potential to be used as building composites. The research was divided in two stages: 1. Investigation on alkali-activated precursor characteristics (bulk chemistry, physical properties of fly ash materials) with research on fly ash mortars with different alkaline activators (through mechanical and morphological analysis). 2. Investigation of possible use of alkali-activated fly ash-based mortars with several levels of calcium in construction sector (through mechanical, microstructural and durability tests). In this thesis, three different fly ash samples are analysed: fly ash from coal combustion (RFA), co-combustion fly ash of coal with wooden biomass (CFA) and fly ash derived from biomass combustion (BFA). These fly ashes offer different chemical and mineralogical compositions, reactivities, densities and particle size distributions. Fly ashes were activated with single activators (sodium hydroxide, quicklime) or combined activators (sodium hydroxide with quicklime, sodium hydroxide with sodium silicate and quicklime with sodium silicate) to obtain pastes and mortars. To analyze the influence of calcium compound on mortar performances, CaO and BFA were added to alkali-activated mortars based on CFA and RFA. This research proved that co-combustion fly ash can be used as a binder in AAMs. The biomass fly ash mortars present poor mechanical properties due to low alumina and silica content. BFA however can be used as a high-calcium additive with retarding properties. The 5% of CaO added to high-silica fly ash AAMs induces decreasing setting time but increasing of material density, mechanical properties and durability. Biomass combustion fly ashes clearly represent promising material for replacing coal fly ashes for specific applications

Influence of alkali activator on mechanical properties of geopolymer mortars from GGBS

Granulated Blast Furnace Slag (GBFS) is alternative sustainable raw material used for production of geopolymer composites. The GBFS is characterized by high level of CaO and SiO2 and after activation with alkaline solution creates a rapid-hardening binder. In this study Granulated Blast Furnace Slag (GBFS) were alkali-activated and examined using strength testing, Thermogravimetric analysis (TGA) and CalorimetryProject Matériaux bio-sourcés et recyclés pour une construction durabl

Requirements for concrete structures in special purpose facilities, based on the example of guidelines for construction

On the basis of the example of a nuclear power plant building, the article compares the structural and materiał standards in place in Poland with the specific requirements concerning concrete structures in such buildings worldwide. Up to 200k cu.m concrete can be used in concrete structures of new generation nuclear power plants. In practice, country codes are used in nuclear power plant design for the reactor technology and main plant and machinery technology supplier, while the actual construction must proceed on the basis of the national legislation applicable to the project site

The effect of cement and aggregate type and w/c ratio on the bound water content and neutron shielding efficiency of concretes

Modeling studies of the effect of cement type, aggregate type and w/c ratio on the bound water amount and shielding properties against neutron ionising radiation of concretes are presented. The change of cement or aggregate type had an significant influence on the bound water amount and neutron linear attenuation coefficient (NLAC) calculated in Monte Carlo N-Particle Transport Code. The multiple regression analysis for the dependent variable NLAC suggested no correlation between w/c ratio and examined parameter.. Data gained in ionic chamber implies an influence of cement type on the concrete shielding properties

Bound water content measurement in cement pastes by stoichiometric and gravimetric analyses

peer reviewedThe cement hydration is one of the most complex processes creating the cement matrix. The degree of hydration is a quantity of Portland clinker with gypsum, that as a whole react with water. For purposes of this analysis it was found to be directly proportional to the bound water in the cement paste specimens. Using the gravimetric method the bound water content was determined in samples by calculating the quantitative loss of the dry specimens weight after igniting to 1000°C and keeping the temperature for 5h. Obtained results were collated with theoretical stoichiometric analysis based on the Bogue and Taylor equations and XRD testing for Portland cement, CEM I 42.5. Obtained outcome has confirmed the relationship between the degree of hydration and the bound water content in cement paste. The influence of the w/c ratio and cement oxide components on bound water quantity were also noticed

Biopolymer Composites as an Alternative to Materials for the Production of Ecological Packaging

The problem of plastic waste has long been a concern for governments and society. However, huge amounts of plastic are still being released into the oceans and the environment. One possible solution is to replace plastics with materials that are more both biodecomposable and biodegradable. The most environmentally friendly materials are made of natural ingredients found in nature, although not all of them can be called biodegradable. In this study, we set out to create a new composite with functional properties that could replace commonly used disposable packaging. To ensure the competitiveness of our solution, we used inexpensive and readily available components, such as gelatin G HOOCCH2CH2C(R1)NHCOCH2NH2 (where R1 is a continuation of the peptide chain), polyvinyl alcohol PVA CH2CH(OH), and glycerin G HOCH2CH(CH2OH)O. The ingredients used in the research come from natural sources; however, they are chemically processed. Some of them, such as polyvinyl alcohol, for example, are biodegradable. With the appropriate selection of the components, in the casting process, the intermixed components made it possible to produce materials that were characterized by good physicochemical properties, including thermal stability, optical transmission of UV-Vis light, cross-linking density, and mechanical strength. The most favorable parameters of thermal stability were observed in casein-containing gelatine forms. The best cross-linking density was obtained in the case of gelatin–glycerine systems. Composite containing caseins distinguished by the highest resistance to flammability, increased thermal stability, flexibility, and greater hardness compared to other composites

Examples of using requirements for construction of nuclear power facilities

The paper presents European examples of the use of requirements for construction of structures in nuclear power facilities. It contains experience in implementing foreign or international detailed requirements in ongoing nuclear projects in Sweden, France, Finland and United Kingdom. The quoted examples show that regardless of the adopted scenario, it is a very complex, expensive and long-term process that requires cooperation of many environments. This is very important from the implementation of the Polish Nuclear Power Program point of view. As announced by the Ministry of Energy its update will be relayed to the Council of Ministers by the end of 201