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Abstract: In this work, an analysis and numerical study have been carried out in order to determine the best candidate brick from the thermal point of view by the finite element method. With respect to the ecological design and the energy saving for housing and industrial structures, there is also a great interest in light building materials with good physical and thermal behaviours, which fulfils all thermal requirements of the new CTE Spanish rule for further energy savings. The conduction, convection and radiation phenomena are taking into account in this study for four different types of bricks varying the material conductivity obtained from the experimental tests. Based on the previous thermal analysis, the best candidate was chosen and then a full 1.05×0.35×1.0m. wall made of these bricks was simulated for fifteen different compositions and temperature distribution is also provided for some typical configurations. The major variables influencing the thermal conductivity of these walls are illustrated in this work for different concrete and mortar properties. The finite element method (FEM) is used for finding accurate solutions of the heat transfer equation for light concrete hollow brick walls. Mathematically, the nonlinearity is due to the radiation boundary condition inside the inner recesses of the bricks. Optimization of the walls is carried out from the finite element analysis of four hollow brick geometries by means of the average mass overall thermal efficiency and the equivalent thermal conductivity. In order to select the appropriate wall satisfying the CTE requirements, detailed instructions are given. Finally, conclusions of this work are exposed. [Copyright &y& Elsevier]

Abstract: In this work numerical structural analysis by the finite element method (FEM) is used in order to study the structural collapse of a Second World War (WWII) lattice tower. The study is divided into two different stages: a forensic pre-diagnostic stage (first) and pathologic analysis and diagnostic stage (second). In the first stage, the causes and the origin of the collapse are determined based on only on the symptoms. In the second stage the failure mechanics are established and these are proven. The entire FEM model is built through beam elements and the design of experiments (DOE) method was employed to limit the number of simulations required, significantly saving on the computational time needed to arrive at a diagnostic. Based on analytical results, it is concluded that the main variables in the structural collapse are: the corrosion of the wire ropes and the wind load. A buckling analysis, both linear and nonlinear, is also carried out to verify and to check that the collapse hypothesis for the communications tower is right. Finally the conclusions of this study are given. [Copyright &y& Elsevier]