Advanced Materials Research Vol. 982

Abstract: This paper gives a brief overview of two different approaches within the inverse analysis used for determination of moisture diffusivity of porous building materials. The inverse methods are represented by Boltzman-Matano approach and genetic algorithms. Both methods are described in this paper and its application is demonstrated on a simple laboratory experiment. Finally, the results of both treatments are compared together and short discussion is given.

Abstract: In the paper is presented calculation of hygric properties of hollow brick block. Namely it is adsorption isotherm, water vapour diffusion resistance factor and moisture diffusivity. The brick block cavities was filled only by air. In first step the properties of brick body were measured. Then the properties of the whole brick block were calculated by using homogenisation techniques.

Abstract: This article discusses about the textile reinforced concrete. The textile reinforced concrete is a new material with great possibilities for modern construction. The textile reinforced concrete consists of cement matrix and textile reinforcement of high strength fibers. This combination of cement matrix and textile reinforcement is an innovative combination of materials for use in the construction. The main advantage of the textile reinforced concrete is a high tensile strength and ductile behavior. The textile reinforced concrete is corrosion resistant. With these mechanical properties can be used textile reinforced concrete in modern construction.

Abstract: Moisture transport in high strength concrete is investigated in this paper. The experiment that involves the water suction is carried out in a long-term. The moisture profiles are measured by non-destructive capacitance method, the last profile is determined gravimetrically. The suction experiment is carried out in isothermal condition at the temperature of 22±1 °C and 25-30% relative humidity.

Abstract: Optical microscopy presents an extension of standard methods for pore space description. In this paper two examples of application in materials and mechanical engineering are introduced. The porosity and pore size distribution of two types of AAC are measured. In the second example the thermally induced cracks of cement fiber composite are visually detected and mathematically described. The technology of sample preparation, measurement technique and digital image processing is described, while advantages and disadvantages are discussed.

Abstract: The aim of this study was to find out an application of the municipal waste incineration materials and try to use them as a replacement for the natural ones. MSWI (Municipal Solid Waste Incineration) bottom ash (BA) was used as partial/total replacement of siliceous sand in CEM II based mortar. Three size fractions of BA were used with respect to replace the siliceous sand in corresponding way. There were designed 5 mixtures with increasing replacement of siliceous sand by 25 % each. The water/cement ratio was decided to be taken according to the constant consistence of the mortar. The bulk density, compressive strength and bending strength of the mortars were decreasing with growing content of BA.

Abstract: In this paper, the effect of elevated temperatures (up to 1000 °C) on thermal properties of two similar types of high-performance concrete containing fine ceramic waste and clay shale, respectively are used as a partial replacement of the cement binder is investigated. Samples were prepared in the same manner and both types of concrete contained from 0 to 60 mass% of either replacement. Both replacements were used in our study as a pozzolana active material which can partially replace cement binder and can improve the final properties of concrete. The aim of this paper is to compare the influence of two different pozzolana active materials on selected thermal properties of high-performance concrete at high temperatures up to 1000 °C. The investigation was performed using the differential scanning calorimetry and these results were supplemented by measurement on horizontal dilatometer.

Abstract: This paper presents a numerical study of earth covered composite arch subjected to internal blast load equaled to 6,25 tons of TNT. The concrete arch was protected against the blast by the 4 or 7 mm corrugated sheet. There was also one simulation where no sheet was applied. It was found that the presence of the corrugated sheet anchored to the arch can reduce 40 % of arch damage compared to the unprotected arch.

Abstract: Although plaster belonged to the first structural materials, they are still getting further enhancements. Nowadays different companies are producing and selling plasters that differ either in their composition or purpose. This article is comparing plasters presented on the market in the Czech Republic. Those are lightweight, renovation and even most common lime-cement plasters. Among the studied characteristics were: basic physical properties (for comparison were measurement of two methods: vacuum water saturation and helium pycnometry); they water vapor transport parameters and heat transport parameters. Lightweight and renovation plasters had shown the biggest porosity, lowest thermal conductivity and the highest diffusion resistance factor.

Abstract: Reverse engineering is a specialization which was developed a lot in the 21^st century. The major aim is researching and describing the principals and procedures of process and structures. Reverse engineering in civil engineering is used to describe the applied loadings which caused corruption or failure of a structure or it is used to reconstruct 3D models of the original object. The aim of this paper is to compare response to static and impact loading of two materials, i.e. plain concrete and high-performance concrete (HPC), with respect to the fracture surface area. These areas were scanned by the 3D laser scanner and they were evaluated in the graphic programs. The main objective of this paper is a presentation of measured data, which can be used to determine the size of the applied loadings using reverse engineering.