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The problem of interaction of the high-velocity solid spherical shock element simulating a micrometeoroid and the combined protective screen including the mesh barrier is considered. The mesh layer is made of steel wire by weaving method. As a result of numerical modeling by SPH method the results of protective wire mesh and projectile destruction behavior are obtained. The effectiveness of several variants of multilayer screen of equal specific mass with different angles of mesh layer orientation is compared.

The value of the modulus of elasticity is very important to know for analyzing the strength of a hot asphalt mixture because the increase in the modulus of elasticity indicates an increase in the ability of a mixture to withstand loads by itself. The use of the wire mesh layer as reinforcement in hot asphalt mixture is considered capable of increasing the modulus of elasticity. The aim of this study was to analyze the relationship between the use of wire mesh layers in the hot asphalt mixture with the modulus of elasticity. The research was conducted using the three-point flexural test apparatus. Based on experiment methode, it was found that hot asphalt mixture with a layer of wire mesh laying 30 mm from the surface of the specimen was the best type of specimen modeling with a bending resistance value of 291.85 KN. The higher the flexural resistance value that can be withheld, the higher the modulus of elasticity, namely 3,800.13 MPa. The best asphalt mixtures are characterized by a high modulus of elasticity, high stress, and low strain.

In this paper, some new original hybrid sandwich beams were built in this way: the core is made with polypropylene honeycomb and the reinforcement is made with steel wire mesh. The connection between the reinforcement and the core was made with epoxy resin. The aim of this study is to create a beam from classic materials but combined in a way to obtain a new and original structure. The static experimental conditions are characterized by bending loading of the beams and the determination of statically stiffness. The dynamic parameters were determined from the beams free vibrations. The next experimental montage was used: the beams were clamped at one end and were left free at the other end. At the free end, a Bruel&Kjaer accelerometer with 0.04 pC/ms−2 sensitivity was placed. A force was applied at the free end to bend the beams and after bending, the force was cancelled and the beams were left to freely vibrate. From the free vibrations recording, the next mechanical parameters were determined: the eigenfrequency of the first eigenmode, the damping factors per unit mass and per unit length, the loss factor, the dynamic stiffness and the dynamic Young modulus.

The paper presents the experimental study on Ferro foam concrete I beam with different number of wire mesh layers. Ferro foam concrete is alternative materials, which consist of a combination between wire mesh and foam concrete. This material is lightweight and easy to be produced. There are 3 specimens has been tested. Specimens’ configuration was 300 mm height, 150 mm width of upper and lower flange, and 60 mm web with 2200 mm span. The different between specimens was number of wire mesh layers, 2 layers, 3 layers, and 4 layers. Foam concrete used in this research consists of cement, water, foam agent, and 10 % Pozzolan. Compression strength of concrete was 23.23 MPa, and Tensile strength of reinforcement D8 and wire mesh G12.7 were 421 MPa. The specimens were tested using four points loading. Three units of LVDT were placed at a distance of 250 mm and 1000 mm from the support. Based on the results, it was found that the maximum load that can be carried out by specimen was 8.48 Tonf, 8.00 Tonf, and 9.50 Tonf, for 2 layer, 3 layers, and 4 layers, respectively. Maximum deflection for each specimen was 14.01 mm, 13.53 mm, and 21.37 mm, for 2 layers, 3 layers, and 4 layers, respectively. Number of layer in I beam 300.60.60 has no significant effect for the beam in their ability to carried the load.

The article is focused on renovation, rehabilitation and reinforcement of high ferroconcrete walls. It tries to point out the experience of experts in solving problems with high ferroconcrete walls. During a revitalization of buildings of a military accommodation facility in Brno with basement and connecting corridors of an average height of 25 m, degradation of concrete, locally missing reinforcement and poor-quality concrete mixtures, the strength class of which varied between C8/10–C10/12, were found in these corridors. Along the height of the pilasters, the structure also showed the signs of torsion and it was assessed the structure also needs to be strengthened/reinforced besides the rehabilitation. The reinforcement structure had to be built from the very foundation of the building, it is linked to the existing wall and has three cascade levels. For the first two parts, a construction pit has been created with a Berliner wall, and these parts reach below the modified terrain, are reinforced with concrete reinforcement according to the structural project, concreted with cast concrete, and the foundation is reinforced with deep-based construction. The second and the third parts of the cascade stretch from the modified terrain between the pilasters to the top and they are made with a two-stage shotcrete technique, the first one has inbuilt concrete reinforcement with welded wire mesh and the second one composite mesh anchored by helical reinforcement without static effect. In terms of the damage of the structure, carbon fibre wrapping technique or grouting of the existing ferroconcrete structure was also used in the affected areas. The article also includes photo documentation of the repairs and structural damage prior to them.

Analytical model has been developed for the shielding effectiveness of a rectangular enclosure with wire mesh covering. The aperture covered by wire mesh is replaced by an equivalent impedance which contains the surface resistance of the wire mesh. Based on the transmission line theory, the enclosure is modelled as a length of rectangular waveguide ended with a short circuit, then the shielding effectiveness (SE) of the enclosure can be calculated. By comparing the calculation with the full-wave simulation software, the proposed method is validated.

In recent days, fibre metal hybrid composites have been utilized for improve the stiffness, excellent corrosion resistance, low density and less weight. CFRP reinforced stainless steel (SS) wire mesh hybrid fibre metal laminate has been fabricated using hand layup process. Viscoelastic properties of fabricated composite samples have been studied by using Dynamic Mechanical Analysis (DMA) test. Mechanical characterization such as Dynamic Mechanical Analysis (DMA), Flexural test and tensile properties of the newly fabricated fibre metal laminated also investigated. The DMA parameters such as storage modulus (E’), loss modulus (E”) and damping factor (tan δ) has been investigated. Flexural test has been performed for evaluating the bending stress. DMA results revealed that storage modulus of E’ was maximum at 5 Hz. In this work tensile strength observed was 533.05 MPa at 16.19 KN. For Flexural strength obtained in the fabricated composite material was 1.03 KN.

Two new experimental studies are presented in this research for improving the convection heat transfer and efficiency of flat plate solar air heater (SAH). An exergetic analysis is applied for evaluating the efficiency of a flat plate (SAH) with and without porous media. It was specially designed, low height bed filled with aluminium wire mesh layers and four aluminium longitudinal obstacles that increase the air path flow through the bed and the area of the absorber plate. Six wire mesh layers as an alternative of absorber plate, the layers had an internal diameter of 0.31 cm and a cross-sectional area of 0.22 cm × 0.22 cm. The wire mesh layers and the obstacles, improve the heat transfer from the absorber mesh layers in the moving air inside the heater. The plotted exergetic efficiency curves are a function of solar intensity, ambient temperature, bed temperature and temperature rise parameter (To-Ti / I). These efficiency curves are in bed with and without porous media through different airflow rate. The results illustrate that the heater with porous media SAH is more efficient, from exergy point of view, then the heater without porous media. The maximum exegetic enhanced efficiency with and without porous media SAH in this study has been found to be 3.42 % and 5.16 %, respectively. These results correspond to the low airflow rate of 0.015 kg/s and 2.5 cm channel depth. A significant improvement in the exergetic efficiency discovered when comparing the proposed system with other conventional SAHs.

It has been established that Adobe provides, in addition to being sustainable and economic, a better indoor air quality without spending extensive amounts of energy as opposed to the modern synthetic materials. The material, however, suffers from weak structural behaviour when subjected to adverse loading conditions. A wide range of mechanical properties has been reported in literature owing to lack of research and standardization. The present paper presents the statistical analysis of the results that were obtained through compressive and flexural tests on Adobe samples. Adobe specimens with and without wire mesh reinforcement were tested and the results were reported. The statistical analysis of these results presents an interesting read. It has been found that the compressive strength of adobe increases by about 43% after adding a single layer of wire mesh reinforcement. This increase is statistically significant. The flexural response of Adobe has also shown improvement with the addition of wire mesh reinforcement, however, the statistical significance of the same cannot be established.

Adobe is an economical, naturally available, and environment friendly construction material that offers excellent thermal and sound insulations as well as indoor air quality. It is important to understand and enhance the mechanical properties of this material, where a high degree of variation is reported in the literature owing to lack of research and standardization in this field. The present paper focuses first on the understanding of mechanical behaviour of adobe subjected to compressive stresses as well as flexure and then on enhancing the same with the help of steel wire mesh as reinforcement. A total of 22 samples were tested out of which, 12 cube samples were tested for compressive strength, whereas 10 beams samples were tested for modulus of rupture. Half of the samples in each category were control samples i.e. without wire mesh reinforcement, whereas the remaining half were reinforced with a single layer of wire mesh per sample. It has been found that the compressive strength of adobe increases by about 43% after adding a single layer of wire mesh reinforcement. The flexural response of adobe has also shown improvement with the addition of wire mesh reinforcement.

Polystyrene waste panel is one of alternative materials that uses polystyrene waste. This experiment is to utilize the polystyrene waste as a non structural panel to be evaluated the ductility. The specimen consisted of cement 250 kg/m3, polystyrene waste was as aggregate, water cement ratio was 0.4 and wire mesh diameter was 0.6 mm with the grid 6 mm × 6 mm placed on the top and bottom of the panels. The polystyrene panels were compressed at 2 MPa. Six specimens had dimension 80 cm length, 30 cm width and the thickness planned were two varieties, they were 0.5 cm and 1 cm. Flexural testing is used to examine load and deflection to measure the ductility. The load and the deflection showed that the maximum load for the specimen with 0.5 cm thickness is 0.4, 0.56 and 0.37. And for 1 cm thickness is 0.4, 0.36, 0.64. It shows that the thickness variation does not give effect on the maximum load. Result showed the average of Displacement Ductility Index of polystyrene waste panels with 0.5 cm thickness was 1.692 and for 1 cm thickness, the average was 4.043. So the average of the panel with 0.5 cm thickness planned is under 1.99 and the panel with 1 cm thickness planned is upper 3, therefore, it is considered imperative for adequate ductility.