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Timber constructions made of round timber components are becoming more and more popular. Given that in the current European standards for the design of timber structures, timber-to-timber joint type is solved only for squared timber. This paper presents results of static tests in tension at an angle of 0°, 90°, 60° to the grain of round timber bolted joints. This research looks into reinforcement with modified washers or self-drilling screws, as these are the least labour-intensive (while economically advantageous). The joints samples were experimentally tested in the laboratory of the Faculty of Civil Engineering VŠB TU Ostrava.

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The effect of waterproof membrane and steel reinforcement protection on the concrete bridge deck is modeled. The attention is paid to the durability prediction related to steel reinforcement corrosion initiation based on the chloride penetration. Thus 2-D finite element chloride ingress model is applied. The transient finite element model serves to solve Ficks second diffusion law using the computer tool compatible with the Matlab environment. The model focuses on the transport of chloride ions through a reinforced concrete bridge deck with and without the effect of waterproof membrane and on an estimate of the concentration of chlorides at the reinforcement level or in places with damage to the epoxide coating of the reinforcement. The model allows the incorporation of damage to the waterproof insulation under the asphalt coating. The time to chloride induced onset of corrosion is predicted and results are compared. The effect of water proof membrane reinforcement protection strategy typical for Central Europe and epoxy-coating protection widely used in North-Western United States is evaluated.

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This article presents the study of structural reinforcement for a building of educational use, known as "Old Type II". The school was built before the creation of the Venezuelan SeismoresistantCovenin 1756. The results of the structural analysis showed insufficient responsiveness to service requests, high vulnerability to seismic action and deficiencies in the quantity and distribution of reinforcing steel. For this reason, the reinforcement of the superstructure was proposed by the construction of panel walls, verifying their action on the existing piloting system. For the modeling, the values of resistance of the concrete obtained in the destructive tests made by the materials laboratory of the School of Civil Engineering of the Universidad Centroccidental Lisandro Alvarado and the soil parameters from the geotechnical study were used.

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This work deals with the revaluation of coffee bean residues from the coffee liquor industry with the aim of developing eco-efficient composite materials with a polymeric matrix of polylactic acid (PLA). The coffee residue is incorporated in a proportion of 20% to the PLA by extrusion. After a grinding process, they are processed by injection to obtain standardized test pieces for their characterization. In order to improve the mechanical properties, as well as the toughness and compatibility between the biopolyester and the lignocellulosic particles of the coffee residue, two oligomers of lactic acid (OLA2 and OLA2mal functionalized with maleic anhydride) are added, together with the particles of the coffee residue during the extrusion process. These "Green composites" show that the incorporation of coffee residue particles from the manufacture of coffee liquor considerably increases the ductility of the samples analyzed by practically 280% due to their high content of oils present in the lignocellulosic residue. In addition, the incorporation of the OLA2 and OLA2mal oligomers contribute to improve the tensile strength of the composite materials studied, by 35% and 60%, respectively. These interesting results show the wide possibilities of this eco-efficient and sustainable material made of PLA and coffee residue. These are biodegradable materials, respectful of the environment and that allow the revaluation of coffee bean residues from the agri-food industry such as coffee liquor.

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This paper describes the use of composite materials in the manufacture of aerodynamic seals. Specifically, the design of the seals between the wing and the belly fairing, made by ALESTIS AEROSPACE, is reviewed for the A350 XWB.In the process, FEM simulations and tests have been performed to obtain the levels of stifness required by the aerodynamic specifications. These tests are made to find the right balance between stifness and adaptability of the seals to the wing geometry, and compliance with the boundary conditions imposed by the pressure difference between the interior of the belly fairing and the exterior (static and dynamic pressure ). Due to the variation of seal boundary conditions, both pressure levels and displacements to be absorbed, in addition to the life requirements, the materials used provide different degrees of rigidity: Matrix: silicone Reinforcements: Polyester fabric Fiberglass fabric Glass composite material Matrix: polyester resin Reinforcement: glass fabric Finish: polyester fabric with low friction treatment The use of suitable combinations of materials allows for lighter and more efficient seals.