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[en] This paper describes and compares results between articles, for this, 4 relevant topics were selected in reinforcements to wood beams of different types and tree origin [1, 2, 3, and 4], found in the literature or status of the Art. On the samples of the literature to be compared, it was considered for the choice that the selected articles have similar approaches and have similar mechanical tests as: tensile strength, resistance to the average flexion, elasticity module analysis, however, a limitation of the work is the fact that the obtained values cannot be bought in an absolute way since the authors and selected referents apply their research on various configurations of wood beams or different species such as Pine, Beech, Alamo and Fir or even the technique and type of fibre to be used in the reinforcement of such fibres as glass, polymer, bamboo, GFRP, and others made from steel, suggesting a percentage comparison of the improvement or efficiency achieved by the applied methods. Concerning the methodological plan it is noted that the selected samples do not use the same units, this is bought according to relative values or percentage of variation according to the type of test, in which a comparison is made with the control sample (beam without backup) and a reinforced or repaired selected beam (which was selected according to the best achieved or as a sample in which the reinforcement is not invasive). The comparison between work referents concludes that these constructive solutions (repair and reinforcement) provide benefits or contributions to the mechanical characteristics of structural elements of wood, shaping an attractive concept for the development of applications in the field of building and civil construction, as: The variation of the elasticity Module, when using a method of repair / reinforcement with organic fibres (the case of Bamboo) is negative . The highest contributions or percentage increases in the elasticity Module and the breakage 126 Module are obtained when synthetic materials are used, for the matter, the GFRP fibre (F. glass + polymer) and the GFRP bar respectively [2 and 3]. The lowest results in the variation of the breakage Module are obtained by using a repair method / reinforcement with glass fibres , however, when using reinforcement with glass materials plus bar polymers, this reaches the highest value on the MOR . The wood beam (Abeto laminate) reinforced with steel bars  represents the highest result of bending resistance
[en] Finite element analysis (FEA) or the finite element method (FEM) (Picture 1) is the product of the digital age in the 1950s by the promotion of digital computers. It is a numerical way  and a computer-based tool that uses mathematical calculations  in a virtual environment  to simulate and analyze products and systems  by engineers and scientists in a different range of industries . This article describes the ways to develop the finite element of each structure by validating its data step by step for doing further studying and modeling. According to different research sources in finite elements methods until the end of January 2019, the finite element method involves modeling the structure by using meshing process , different range of properties, verified data [3–5], and different software according to its purposes . Moreover, the most important step after modeling is a validation of the model by testing decompression and stabilization procedures  thereby comparing with experimentally validated data. The modeling method introduced in this study can be used for future analysis and modeling in a wide range of industries, biomechanics, and buildings since it benefits from handling any mathematical or physical problem [4, 7], optimizing performance, designs and cost, reducing the development time, testing , the number of physical prototypes  , and material usage , improving safety, information  and quality , having freedom to select the elements, its functions  and different materials , and making complex geometrical calculations . The adoption of this method makes it easy to predict the product performance and reliability, determine the role of material properties and behavior [10–12] and perform parametric analysis of loadings
[en] Building quality control is today one of the key points of construction in Spain. As regards the manufacture of construction products or other products and manufacturing systems, the regulation in this aspect of quality control is much greater. In the present study, a normative analysis of the different phases of development of carbon fibers was carried out, from manufacturing to commissioning. Among different regulations regarding quality control in the manufacture of carbon fibers (FRP) for buildings, we refer to the American standard CNR-DT 200 R1 / 2012, regarding the different manufacturing processes of carbon fibers , being of three types: By poltrusión, by systems of lamination or by humid accumulation. Also in this same standard, reference is made to the quality control in the installation of carbon fiber, since it emphasizes the importance of the preparation of the surface where it is going to be applied, since they are systems externally attached to the support or functional element. In this same manufacturing process, the UNE EN 14889-2: 2006 Standard establishes minimum control requirements in the product resulting from this manufacture, establishing a production control system in the factory, which must consist of procedures, regular inspections, tests and / or evaluations and the use of test results to control raw materials, equipment, and the product. Finally, the implementation of the carbon fibers has as a premise the preparation of the support, since adhesion to the support is essential for the proper functioning of the system, as well as establishing acceptance criteria of the support, atmospheric conditions, resin preparation and in situ testing.
[en] A procedure to increase the compressive strength of concrete consists of its confinement by carbon fiber fabrics bonded externally with epoxy resins. In this way, a structural system is obtained that increases in a very remarkable way its resistance and ductility with respect to the base material. There are different models to estimate the compressive strength of confined concrete [1-3]. All these models have been experimentally calibrated and in them the characteristics of the confinement material intervene. However, they are not able to predict in a solvent way the effect of the confinement when the concrete moves in a fork of important resistances. Figure 1 shows the experimental results obtained for confined concretes of medium and low resistances and the values estimated by different regulations. It can be verified how the values obtained experimentally (EXP) differ significantly from those estimated by different standards. In this work, the compression resistance of concrete of low and medium resistances confined with carbon fiber fabrics has been evaluated experimentally. Different existing models have been analyzed to predict the strength of confined concretes and the experimental results obtained have been compared with the values estimated by the models of these documents. The analysis of the results allows to identify the models that best fit the experimental values obtained.
[en] The resistance of concrete to compression can be increased very importantly by its confinement. The confinement of the concrete by means of the external gluing of high resistance fiber fabrics is a technique that has been known for decades and is increasingly used in reinforcement works of structural elements subjected to compression. Carbon fiber fabrics are commonly used, due to their high strength and high modulus of elasticity. The break of the elements occurs when the tensile fiber fails. There are different models to predict the compressive strength of concrete confined with this type of fabric. In America, the model proposed by the ACI  is usually used, while in Europe, the one proposed by the FIB is used . In both models, the strength of the confined concrete is obtained from the geometry and strength of the unconfined concrete and the geometric and mechanical characteristics of the fabric that confines the concrete. However, the expressions used are conceptually different. Table 1 shows the expressions contributed by both associations for circular section elements...
[en] This paper analyzes the differences existing in Annex 14 of Instruction EHE 08 Recommendations for the use of concrete with fibers between the quality control of conventional concrete (HC) and that of concrete reinforced with steel fibers (RCSF).
[en] This paper analyzes the possibility of redistributing stresses in reinforced concrete structures with steel fibers (SFRC) in comparison with conventional concrete structures (CC). Instruction EHE 08  allows during the structural analysis to perform a limited redistribution of the loads calculated in elastic and linear regime that satisfies the equilibrium conditions and always linked to ductility conditions of the critical sections that guarantee the necessary deformations for the laws of solicitations adopted after redistribution . The level of redistribution allowed by Instruction EHE 08 depends on the relationship between the depth of the neutral fiber and the useful edge of the section. This magnitude is closely related to the plastic turning capacity of the section. In a CC the plastic turning capacity is conditioned by the ultimate deformation of the concrete, 3.5 ‰, or by the ultimate deformation of the steel 10 ‰. In the vast majority of occasions the ultimate deformation of the concrete is the one that fixes the plastic turning capacity, since the deformation of the steel is reached before that of the concrete for relations x /d≤0.29, a value that is rarely reached in the practice. In SFRC the ultimate deformation of the concrete is much higher than 3.5 ‰, so the turning capacity is also. This means that with the same depth of neutral fiber, the turning capacity of an EHRFA is higher than that of an CC. The redistribution capacity of a CC armed with a B500SD steel is given by the following expression of EHE 08:
[en] In this work, the conditions of self compactability of a self-compacting concrete reinforced with steel fibers have been experimentally evaluated. The concrete has been manufactured by LAFARGEHOLCIM, for its elaboration it has been used CEM II/A-M (P-V) 42.5 R cement manufactured by Lafarge, with a content of 350 Kg/m3 and a water cement ratio of 0.56. Plasticizers (1.9) and super plasticizers (5.8) have been added as additives. As reinforcement, cold drawn steel fibers of 50 mm length and 0.62 mm diameter (slenderness 80.6) have been used, with a dosage of 10 kg/m3, supplied by the company Bekaert with the commercial name Dramix. To guarantee that the studied concrete has the necessary characteristics to be able to catalogue it as self-compacting, we have carried out the tests of runoff, funnel in V, box in L and runoff with ring J according to the instruction EHE-08 . Figure 1 shows the performance of the runoff test...
[en] UNE-EN 13374 Temporary Edge Protection Systems Product Specification, Test Methods, classify temporary edge protection systems (TEPS) in three classes (A, B and C), depending on the inclination of the work surface and the height of fall. The standard establishes geometrical and mechanical requirements that the TEPS must overcome depending on their classification. Class A systems, which are the most widely used, can only be used when the angle of inclination of the work surface is less than 10 °. The regulations are written for wooden or metallic elements, but they do not exclude the use of any other material.
[en] This paper analyze the differences between the quality control of conventional concrete (CC) and that of steel fiber-reinforced concrete (SFRC), according to Annex 14 of the Spanish Structural Concrete Code EHE 08 Recommendations for the use of concrete reinforced with fibers