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Fire reasistance of load-bearing wooden structures is evaluated by the charring of surface layers of wooden bearing elements. Fire protection cover plays important role. Gypsum palsterboard and gypsum fibrebords were investigated. Influence of fire was by standard time-temperature curve represented, both in the fire furnace and through mathematical analysis.

This study addresses the issue of the resistance to high temperatures of lightweight concrete lightweighted with sintered fly ash aggregate. Lightweight concretes with different amounts of lightweighting and their properties after loading temperatures of 600, 800 and 1000 °C were investigated. In particular, the effect of high temperature on the mechanical properties of the concrete was determined on the test specimens, and the effect on the microstructure was investigated by X-ray diffraction analysis and scanning electron microscopy. It was found that there is an increase in compressive strength between 0 and 21% up to 800 °C, where the increase in strength decreases with increasing degree of lightening. At 1000 °C, the internal structure of the lightweight concrete destabilized, and the compressive strength decreased in the range of 51–65%. After loading at 1000 °C, the scanning electron microscope showed the formation of spherical-shaped neoplasms, which significantly reduced the internal integrity of the cement matrix in the lightweight concrete due to the increase in their volume. It was found that the lightweight concretes with higher lightweighting showed significantly less degradation due to higher temperature.

Today, lightweight concretes with lightweight expanded aggregates (expanded clay, agloporite) are most commonly used. This paper deals with the production of lightweight concretes lightweighted with foamed glass-based aggregates. Foamed glass is a lightweight material characterised by a very good ratio of thermal insulation and mechanical properties. Foamed glass is made of approximately 90% recycled glass waste (mostly mixed), which cannot be used in any other way, as well as water glass and glycerine. When concrete is lightened with foamed glass, these concretes achieve unique properties while conserving primary aggregate resources, avoiding landfilling of glass waste and efficiently using the waste material to produce lightweight concrete with higher added value. The paper discusses the possibilities of developing lightweight structural concretes using glass foam based aggregates to achieve higher strength classes while reducing the weight and thermal conductivity of the concrete. As part of the research work, new types of lightweight concrete with a bulk density in the range of 1750 - 1930 kg/m3 and a thermal conductivity from 0.699 to 0.950 W / (m.K) were developed., TDnes se nejčastěji používají lehké betony s lehkým expandovaným kamenivem (keramzit, agloporit). Tento příspěvek se zabývá výrobou lehkých betonů lehčených kamenivem na bázi pěnového skla. Pěnové sklo je lehký materiál vyznačující se velmi dobrým poměrem tepelně izolačních a mechanických vlastností. Pěnové sklo je vyrobeno z cca 90 % recyklovaného skleněného odpadu (většinou smíšeného), který nelze jinak využít, stejně jako vodní sklo a glycerin. Když je beton vylehčován pěnovým sklem, dosahují tyto betony jedinečných vlastností a zároveň šetří primární zdroje kameniva, zabraňují skládkování skleněného odpadu a efektivně využívají odpadní materiál k výrobě lehkého betonu s vyšší přidanou hodnotou. Článek pojednává o možnostech vývoje lehkých konstrukčních betonů s použitím kameniva na bázi pěnového skla pro dosažení vyšších pevnostních tříd při snížení hmotnosti a tepelné vodivosti betonu. V rámci výzkumných prací byly vyvinuty nové typy lehkých betonů s objemovou hmotností v rozmezí 1750 – 1930 kg/m3 a tepelnou vodivostí od 0,699 do 0,950 W/(m·K).

Foam glass is currently a material produced from waste glass that cannot be used in the glass industry. Therefore, it is currently made from secondary raw materials obtained by recycling unusable waste glass. Due to the large proportion of closed pores in the material structure, the foam glass achieves excellent thermal insulation properties and limited water absorption. The porous structure of the glass is relatively regular, and the pores predominantly have a round character; therefore, the foam glass exhibits very good mechanical properties at a low density. Foam glass in the form of aggregate represents an interesting raw material from which it is possible to produce various types of light composites with a very good ratio of thermal insulation and mechanical properties. The contribution describes the results of research in the field of the development of ultra-lightweight aggregate concretes with subsequent use for producing prefabricated thermal insulating masonry elements for the construction of energy efficient buildings.

As part of research works devoted to the development of silicate thermal insulation materials, two mixtures of plasters based on lightweight aggregate and on traditional and alternative binders were designed. The laboratory-prepared plasters were applied to masonry columns, in which probes were incorporated for monitoring changes in moisture. After the plasters had hardened, the structure fragments were flooded with water of a constant level for the whole duration of the long-term measurement. For monitoring the moisture profile, 2 methods of measurement were used. It was electrical impedance spectrometry and determination of moisture content using a capacitive hygrometer., V rámci výzkumných prací věnovaných vývoji a výzkumu silikátových, tepelně izolačních materiálů byly navrženy dvě receptury omítek na bázi lehkého kameniva a jak tradičních, tak i alternativních pojiv. Laboratorně připravené omítky byly aplikovány na zděné sloupky, ve kterých byly zabudovány sondy za účelem sledování vlhkostních změn. Po zatvrdnutí omítek byly fragmenty konstrukce zatopeny vodou o konstantní výšce, po celou dobu dlouhodobého měření. Pro sledování vlhkostního profilu byly použity 2 metody měření, jednalo se o elektrickou impedanční spektrometrii a dále o stanovení vlhkosti pomocí kapacitního vlhkoměru.