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The article discusses the problem of influence of salt concentration on building material moisture readouts using the microwave technique. The content of the paper covers the description of the problem of salt ions presence in the structure of the brick masonries of the buildings and sources of salinity. Additionally, the physical description of microwave detection method is discussed together with the underline of the phenomenon of signal attenuation due to salt ions presence. In the results section, the readouts showing the dependence between moisture readouts of bricks that differ in salt concentration are presented and suitable conclusions are formulated. [ABSTRACT FROM AUTHOR]

The article presents two techniques of moisture detection in the porous building materials. The content of the paper covers the description of detection methods and comparison of the exemplary readouts achieved using two type of sensors. The readouts present the dependence between red brick volumetric water content, evaluated gravimetrically and the apparent permittivity values determined by both sensing techniques. Using the achieved data, calibration models are evaluated and the quality of both models is determined. The aim of the article is to show the measuring potential of both sensing techniques and emphasize their advantages and disadvantages. [ABSTRACT FROM AUTHOR]

Hemp-lime composite is mainly used as thermal insulation for walls. As a wall material, it is exposed to the influence of rainwater and groundwater through capillary action. Due to the high content of highly porous organic filler (hemp shives), the material is characterized by high water absorption. Despite the presence of a lime binder, the action of increased moisture may lead to the development of biological corrosion. It is advisable to look for ways to reduce water absorption. The study involved modification of the binder with the admixture of biopolymer in the form of gum arabic in the amount of 1% and 3% (as a partial substitute for the binder). It is a natural resin that hardens in air. The influence of the modification was verified on the basis of the mass water absorption and capillary rise tests using gravimetric and TDR method. [ABSTRACT FROM AUTHOR]

This paper presents the results of testing popular composite materials used for FDM printing. The copolymers used for the analysis were acrylonitrile-butadiene-styrene (ABS) and polylactide (PLA). A 3D printer placed in a transparent chamber equipped with electronic probes to record the temperature within the print head, work table, and volume was used to prepare the prints. The 3D model for the study was designed in Autodesk's Inventor software and a preliminary dynamic simulation of uniaxial tension was performed using the finite element method (FEM). The simulation was used to predict von Mises stresses and strains in the test specimens. The specimens were subjected to static tensile testing on a testing machine and the simulation results were compared with the results of laboratory tests of the printed parts. The research aimed to obtain information on the mechanical properties of selected composite materials intended for use in the construction of components of laboratory bioreactors. [ABSTRACT FROM AUTHOR]

The paper comprises the presentation of non-invasive and non-contact microwave measurement method in order to estimate the humidity of building materials. The content of the paper covers information concerning the phenomena related to propagation of electromagnetic waves in building materials, introduction of non-invasive and non-contact measurement method with the use of wideband microwave signals and presentation of the exemplary moisture measurement results achieved by red brick examination. [ABSTRACT FROM AUTHOR]

The building sector is responsible for 32% of global energy consumption and 19% of all energy-related greenhouse gas emissions. Uninsulated existing buildings, including industrial ones constitute the greatest threat to reducing greenhouse gases. The requirements for some of them are difficult to fulfill, resulting from the age of these buildings, which are treated as historic buildings and require preservation of the facade in an unchanged form. The process of performing a full energy audit is long and expensive; hence, the authors present the methodology supporting the reduction of the energy consumption of buildings implemented in BIM design programs. It has been shown that working in this environment allows performing a multivariate thermal simulation of an object based on the analytical 3D models. As a result of these work it is possible obtain reports divided into zones and spaces which contain detailed loads analysis for the project. It is expected that the proposed analysis tool will assist researchers and practitioners in better understanding BIM environment, as an application supporting the reduction of the energy consumption of buildings. [ABSTRACT FROM AUTHOR]

The diffusion of calcium ions Ca2+ in aquatic solutions (10 g/l) was measured for two brick samples from a region in Bohemia (Vysoké Mýto, Holešov-Žopy). The experiment was performed under laboratory conditions at the ambient temperature of 20 ± 2 °C for a period of 240 h. The bricks were cut into three depth layers. The calcium concentrations were analyzed chelatometrically. The biodegradation potential of the individual layers was also studied. The results indicated that the depth and quality of firing are of importance regarding the transport of calcium, and they affect the success of bio-colonization. [ABSTRACT FROM AUTHOR]

The hemp-lime composite is mainly used as wall insulation material in timber frame structures. Due to the highly porous aggregate in the form of hemp shives, this material is characterized by high water absorption. The absorbed water adversely affects the parameters of the composite, including the decrease in thermal insulation and mechanical strength parameters. The article presents an analysis of the influence of the modification of lime based binder with casein on the reduction of water absorption and capillary rise of a hemp-lime composite. Casein is a protein of animal origin, used in ancient times in lime mortars to improve their mechanical strength and resistance to water. The capillary rise test was performed using TDR probes (Time Domain Reflectometry) and the gravimetric method. [ABSTRACT FROM AUTHOR]

The article attempts to determine the best working conditions for desktop 3D printers with printing chamber. For the analysis, the polymer materials acrylonitrile-butadiene-styrene (ABS) and polylactide (PLA) as two most commonly used copolymers in 3D printing. The work presents the types of filaments and compares them in terms of shrinkage, which is a disadvantageous phenomenon and occurs especially in prints made of materials for which higher temperatures of the table and the print head are set. A 3D printer placed in a chamber made of acrylic glass was used to carry out research on improving the quality of prints. The chamber is equipped with electronic probes that allow to record the temperature within the head, the working table and the chamber volume. To monitor the printer's operation, a CCD camera was used with a view of the workstation in real-time mode with the possibility of video recording. The analysis of the results of the conducted research allowed for the assessment of the parameters that should be taken into account, and which correct selection eliminates failures during the printing process and guarantees better quality of the final print. [ABSTRACT FROM AUTHOR]