Determining Concrete Composition on Recycled Aggregates

abstractPL: -abstractEN: The problem of recycling of construction wastes is important and at the same timedifficult to deal with. One of the possible ways of using the construction wastes coming from thedemolition of concrete constructions is to re-use them in the production of construction concretes asrecycled concrete aggregates RCA. Determining the concrete composition with the use of RCAdemands conditioning its different from the natural aggregates NA physical and mechanicalproperties. In the procedure of projecting the concrete composition with three equations theory theassumption of consistency class of concrete mixture is demanded. Having accepted it, the waterdemand of aggregates and cement is determined. In case of natural aggregates NA the formulas ofSterne's and Bolomey's are used in which aggregates water demand is conditioned from its kind andgranulation and also from concrete mixture consistency. In case of RCA, there is lack of such dataand each time it is necessary to determine the water demand empirically after performing a trialbatch. There also exists a necessity to determine the relation between RCA water demand and itsother properties which are easy to be determined in laboratory conditions and in short time. Such aproperty can be measured with the crushing rate wrm resistance of aggregates to crushing. Crushingrate wrm was used to qualify the recycled aggregates from recycling with the point of their potentialof being re-used in constructive concrete production. It was determined a relation between crushingrate wrm and the coefficient ARCA taking place in the modified strength equation of Bolomey and thusit became possible to use the method of three equations to project the concrete composition onrecycled aggregates.score: 8collation: 266-27

Analysis of selected properties of warming system prepared with various plastering mortar

Nowadays, one of the most important challenge in civil construction is design, build and use buildings in sustainable development way. This article describes one of the most important thermo-modernization undertaking, which is increase of insulation of external walls. The research was prepared in special technology on samples with silicon, mineral, acrylic thin-layer plasters and with adhesive mass only. Purpose of the research was to analyze the physical and mechanical properties of the additional layer with this four variants of plastering mortar. The research, which was made by authors showed that the thin – layer plasters are characterized by resistance to environmental factors, which they are directly exposed. The connection between the individual layers of the thermal insulation system secures durability of the plasters. The samples with mineral plastering mortar were characterized by the highest interlayer adhesio

Ocena i normowanie rozwiązań technologiczno-organizacyjnych procesów budowlanych

This article refers to the analytical researching of the processes of work to establish the rational manners for realizations and standardization models for work planning.Przedmiotem opracowania są zagadnienia analityczne badania procesów pracy w celu ustalenia racjonalnych sposobów ich realizacji oraz modele ich normowania na potrzeby planowania robót

Analysis of selected properties of warming system prepared with various plastering mortar

Nowadays, one of the most important challenge in civil construction is design, build and use buildings in sustainable development way. This article describes one of the most important thermo-modernization undertaking, which is increase of insulation of external walls. The research was prepared in special technology on samples with silicon, mineral, acrylic thin-layer plasters and with adhesive mass only. Purpose of the research was to analyze the physical and mechanical properties of the additional layer with this four variants of plastering mortar. The research, which was made by authors showed that the thin – layer plasters are characterized by resistance to environmental factors, which they are directly exposed. The connection between the individual layers of the thermal insulation system secures durability of the plasters. The samples with mineral plastering mortar were characterized by the highest interlayer adhesio

Influence of the Calcination Temperature of Synthetic Gypsum on the Particle Size Distribution and Setting Time of Modified Building Materials

The paper assesses the influence of the calcination temperature of synthetic gypsum binder on the binding properties of innovative gypsum pastes, as well as on masonry and plastering mortars. The calcination process of gypsum binder was carried out at four different temperatures ranging from 170 to 190 °C. The specimens for testing were prepared on the basis of the obtained raw material with a constant water to gypsum ratio of w/g = 0.75. It was noted that the calcination temperature influenced the setting time of the gypsum. Based on synthetic gypsum, mixtures of masonry and plastering mortars modified with tartaric acid and Plast Retard were designed. During the experiment, the particle diameter distribution of aqueous suspensions of building and synthetic gypsum particles (before and after calcination) was determined using the Fraunhofer laser method. The dimensions of the obtained artificial gypsum grains did not differ from the diameters of the gypsum grains in the reference sample. On the basis of the conducted research, it was found that the waste synthetic gypsum obtained in the flue gas desulphurization process met the standard conditions related to its setting time. Therefore, it may be a very good construction substitute for natural gypsum, and consequently, it may contribute to environmental protection and the saving and respecting of energy

High Performance Concretewith SCM and Recycled Aggregate

score: 8collation: 233-24