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Heterogeneous and micro-structured materials have been the object of multiscale and homogenization techniques aimed at recognizing the elastic properties of the equivalent continuum. The proposed investigation deals with the mechanical characterization of the heterogeneous material structured metamaterials through analyzing the ultimate strength using the limit analysis of the Representative Volume Element (RVE). To get the desired material strength, a novel finite element formulation based on the derivation of self-equilibrated solutions through the finite elements devoted to calculating the lower bound theorem has been implemented together with the limit analysis in Melàn’s formulation.

The finite element formulation is based on discrete mapping of Volterra dislocations in the structure using isoparametric representation. Using standard finite element techniques, the linear operator V, which relates the self-equilibrated internal solicitation to displacement-like nodal parameters, has been built through finite element discretization of displacement and strain.

The proposed work presented an elastic homogenization of the mechanical properties of an elementary cell with a geometry known in the literature, the isotropic truss. The matrix of elastic constants was calculated by subjecting the RVE to numerical load tests, simulated with a commercial FEM calculation code. This step showed the dependence of the isotropy properties, verified with Zener theory, on the density of the RVE. The isotropy condition of the material is only achieved for certain section ratios between body-centered cubic (BCC) and face-centered cubic (FCC), neglecting flexural effects at the nodes. The density that satisfies Zener’s conditions represents the isotropic geomatics of the isotropic truss.

For the isotropic case, the VFEM procedure was used to evaluate the isotropy of the limit domain and was compared with the Mises–Schleicher limit domain. The evaluation of residual ductility and dissipation energy allowed a measurement parameter for the limit anisotropy to be defined. The novelty of the proposal consisted in the formulation of both the linearized and the nonlinear limit locus of the material; hence, it furnished the starting point for further limit analysis of the structures whose elementary volume has been described through the proposed approach.

In the analysis of structures in a fire situation by simplified and analytical methods, one assumption is that the fire resistance time is greater than or equal to the required fire resistance time. Among the methodologies involving the fire resistance time, the most used is the tabular method, which associates fire resistance time values to structural elements based on minimum dimensions of the cross section. The tabular method is widely accepted by the technical-scientific community due to the fact that it is safe and practical. However, its main criticism is that it results in lower fire resistance times than advanced thermal and thermostructural analysis methods. The objective of this study was to evaluate the fire resistance time of reinforced concrete beams and compare it with the required fire resistance time recommended by the tabular method of NBR 15200 (ABNT, 2012).

The fire resistance time and required fire resistance time of reinforced concrete beams were evaluated using, respectively, numerical models developed based on the finite element method and the tabular method of NBR 15200 (ABNT, 2012). The influence of the following parameters was investigated: longitudinal reinforcement cover, characteristic compressive strength of concrete, beam height, longitudinal reinforcement area and arrangement of steel bars.

Among the evaluated parameters, the covering of the longitudinal reinforcement proved to be more relevant for the fire resistance time, justifying that the tabular method of NBR 15200 (ABNT, 2012) being strongly and directly influenced by this parameter. In turn, more resistant concretes, higher beams and higher steel grades have lower fire resistance time values. This is because beams in these conditions have greater resistance capacity at room temperature and, consequently, are subject to external stresses of greater magnitude. In some cases, the fire resistance time was even lower than the required fire resistance time prescribed by NBR 15200 (ABNT, 2012). Both the fire resistance time and the required fire resistance time were not influenced by the arrangement of the longitudinal reinforcements.

The present paper innovates by demonstrating the influence of other important design variables on the required fire resistance time of the NBR 15200 (ABNT, 2012). Among several conclusions, it was found that the load level to which the structural elements are subjected considerably affects their fire resistance time. For this reason, it was recommended that the methods for calculating the required fire resistance time consider the load level. In addition, the article quantifies the security degree of the tabular method and exposes some situations for which the tabular method proved to be unsafe. Moreover, in all the models analyzed, the relationship between the span and the vertical deflection associated with the failure of the beams in a fire situation was determined. With this, a span over average deflection relationship was presented in which beams in fire situations fail.

This study aims to analyze the responsible consumption of Generation Z and millennials in the Latin American market, with special emphasis on the Peruvian case, to identify their differences with consumers born in 1980 and earlier and to evaluate their contribution to Sustainable Development Goal 12.

The study was conducted on a sample of 309 persons living in Lima. After developing and validating an instrument, an online questionnaire was used to collect data. These data were analyzed descriptively and inferentially, using chi-square tests to validate the relationship between variables.

The study identifies and explains the new trend of responsible consumption among Generation Z and millennials in emerging markets, where end consumers interact with and prefer products and services from companies that demonstrate responsible behavior and offer trust. It identifies new consumption variables that go beyond the traditional ones.

The study reveals a trend in the responsible consumption of Generation Z and millennials in Peru. However, it is necessary to complement the study in other countries in the region, as well as to study the new generations, such as the alpha generation and their consumption patterns.

The new trend of responsible consumption among Generation Z and millennials is forcing companies to implement strategies and develop corporate social responsibility programs. These companies must demonstrate ethical, environmental, socially responsible and sustainable behaviors in their daily operations to satisfy their stakeholders.

The study reveals a new trend in Peru, a developing country, where the market – the end consumer – is more informed and therefore demands better corporate performance from companies, including care for the environment and a contribution to society that includes a good relationship with its stakeholders.

Analizar el consumo responsable de la Generación Z y Millennials en el mercado latinoamericano, con especial énfasis en el caso peruano, con el fin de identificar sus diferencias con los consumidores nacidos en 1980 y antes y evaluar su contribución al Objetivo de Desarrollo Sostenible (ODS) 12.

El estudio se realizó sobre una muestra de 309 personas residentes en Lima. Después de desarrollar y validar un instrumento, se utilizó un cuestionario en línea para recopilar datos. Estos datos fueron analizados de forma descriptiva e inferencial, utilizando pruebas de chi-cuadrado para validar la relación entre variables.

El estudio identifica y explica la nueva tendencia de consumo responsable entre los Millennials y la Generación Z en los mercados emergentes, donde los consumidores finales interactúan y prefieren productos y servicios de empresas que demuestran un comportamiento responsable y ofrecen confianza. Identifica nuevas variables de consumo que van más allá de las tradicionales.

El estudio revela una nueva tendencia en Perú, un país en desarrollo, donde el mercado -el consumidor final- está más informado y por tanto exige a las empresas un mejor desempeño corporativo, incluido el cuidado del medio ambiente y un aporte a la sociedad que incluye una buena relación con sus clientes y partes interesadas.

El estudio revela una tendencia en el consumo responsable en la Generacion Z y Millennials en el Perú. Sin embargo, es necesario complementar el estudio en otros países de la región, así como estudiar las nuevas generaciones, como la generación alfa, y sus patrones de consumo.

La nueva tendencia de consumo responsable entre la Generación Z y Millennials y obligando a las empresas a implementar estrategias y desarrollar programas de responsabilidad social corporativa. Estas empresas deben demostrar comportamientos éticos, ambientales, socialmente responsables y sostenibles en sus operaciones diarias para satisfacer a sus grupos de interés.