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The substantial increase in extreme weather events in recent decades, especially hurricanes and tropical cyclones, constitutes a threat to the Caribbean region. The impact of these phenomena on houses and buildings with light roofs has increased considerably in recent years. The objective of this research is to describe a procedure that allows the numerical simulation of light metal roofs in the aspect of static and dynamic loads typical of extreme winds, in order to obtain criteria about the limit stresses and deformations to which they are subjected, which facilitate the decision-making process. Systems analysis and synthesis methods were used, as well as finite element modeling and simulation. The dynamic analysis of the wind loads made it possible to simulate the real behavior of the light roofs. It was shown that the highest stress values are concentrated in the area near the holes in the roof, constituting the weakest point where the failure of the metallic light roof begins. The results show that the proposed procedure facilitates decision making in the search for constructive solutions that minimize these effects. [ABSTRACT FROM AUTHOR]

A linear dynamic study of the tensional status of the unloading conveyor's spin beam in the new model CCA-5000 Cuban sugarcane harvester is carried out. The dynamic coefficients were determined using a strain gauge experimental evaluation of the KTP-23 harvester, which is a similar model in structure to the CCA-5000. A finite elements analysis is used to obtain the safety distribution factor and the tensions in the beam for different load combinations linked to a dynamic variation curve of the loads. Aiming to verify the presence or not of large amplitudes on the system oscillations caused by the resonance phenomenon, an analysis of the frequency modes for each load status is conducted, and the results are compared with the terrain irregularities frequencies on which the harvester moves. Finally, taking into account the previous results, the shape of the beam is optimized in order to decrease its steel volume. [ABSTRACT FROM AUTHOR]

A linear dynamic study of the tensional status of the unloading conveyor´s spin beam in the new model CCA-5000 Cuban sugarcane harvester is carried out. The dynamic coefficients were determined using a strain gauge experimental evaluation of the KTP-23 harvester, which is a similar model in structure to the CCA-5000. A finite elements analysis is used to obtain the safety distribution factor and the tensions in the beam for different load combinations linked to a dynamic variation curve of the loads. Aiming to verify the presence or not of large amplitudes on the system oscillations caused by the resonance phenomenon, an analysis of the frequency modes for each load status is conducted, and the results are compared with the terrain irregularities frequencies on which the harvester moves. Finally, taking into account the previous results, the shape of the beam is optimized in order to decrease its steel volume. [ABSTRACT FROM AUTHOR]

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In the present work a study of the state of stress and deformation of the steering system of the new model of Cuban sugarcane harvester CCA-5000 is performed. The curve of variation of the extreme loads acting on the system from the strain experimental evaluation was performed to model sugarcane harvester KTP-23 in an test track, where the dynamic coefficients produced were determined was used in different parts of this. For this study, the Finite Element Method was used. Through linear dynamic analysis was determined the cause of the breakage what happened in hinge system in test technological and operation of the new sugarcane harvester to appear stresses of 212,4 MPa in the same test, being the yield strength of the steel used in manufacture of 210 MPa. The analysis of a new design of this system is performed, getting a safety factor of 2,11; at the same time analyzing frequency modes of both models and the results are compared with the frequencies of the irregularities of the land by where the sugarcane harvester is moved, in order to verify the presence or absence of large amplitude oscillations in the system by the resonance phenomenon. [ABSTRACT FROM AUTHOR]

Welded joints are an important component in structures, by this reason is necessary to know the behaviour of these elements under cyclic loads. The objective of this work is to obtain the S-N curve of the butt welded joint of AISI 1015 steel and electrode E6013 as the contribution material. Fatigue test was realized within the ASTM standard in the MTS810 testing machine. Rectangular cross section specimens was used. Cyclic loads was asymmetric tensile and the asymmetry ratio used was 0,1. In this study was obtained the fatigue limit equal to 178 MPa, at the cut point of 2 039 093 cycles. [ABSTRACT FROM AUTHOR]

The objective of this work was the determination of the state of the dynamic loads in several models of the support of the system of automatic pilotage of an underground train with the employment of the Method of the Finite Elements starting from the spectral density of power of the loads and the maximum accelerations determined previously in extensometrics evaluations carried out to the same one, keeping in mind the frequencies characteristic of oscillation of the group of high frequency (HF for its initials in English). As a result of this investigation it was determined that the high values of tensions that they appeared in this element they were the cause of the appearance of the cracks and its development resulted in the appearance of high levels of vibrations, what bore to the decontrols in the operation of the system and the necessity of its repair or premature substitution. It was designed and a new model of support, more rigid, analyzed where together with the elevation of the resistance, is improves her behavior notably before the dynamic loads. [ABSTRACT FROM AUTHOR]

This paper presents the results obtained for the calculation of stresses by means of the finite element method in a compact test specimen. Two geometric models were obtained to perform the simulations. For the first one, a real specimen was scanned using a 3D scanner Konika Minolta Range 7, while for the second an ideal specimen was modeled using the software SolidWorks. It was necessary to carry out a study of the mesh convergence to determine the size of the finite element to be use around the crack in each specimen. In this way it was obtained that for the scanned specimen the size of finite element to be used was of 1,2 mm, whereas for the modeled one was of 1,4 mm. It was obtained the maximum stresses and displacements to both models with a percentage error between the stresses of 7,84%. [ABSTRACT FROM AUTHOR]