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[EN] The design of bending-active structures is a challenging problem, due to the high non-linearity of the activation process, the coupling between member sizing, structural shape and the deformability and buckling sensitivity inherent in the resulting lightweight configurations. Due to the large number of form-finding variables, the choice of member sizing is one of the main difficulties at the conceptual phase. In this paper, authors propose a design tool to generate efficient structural configurations for braced bending-active tied arches using multi objective optimization strategies. Initially, a non-linear FE analysis is performed for each plausible configuration and at each generation of the optimization algorithm. In a second step, a genetic algorithm classifies the solutions and establishes new structural configurations according to best performance. Solutions are evaluated in terms of stresses in the active member and cables, and maximum deflections, as required by design codes for pedestrian bridges. Results are given in terms of non-dimensional parameters, in order to make them applicable to a wide variety of scales ; The authors gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through grant BIA2015-69330-P (MINECO), the European Union programme through grant ERASMUS Traineeships 2017 - E+ and the support from CALTER Ingenieria and SOFiSTiK AG for providing a software license ; Bessini, J.; Shepherd, P.; Monleón Cremades, S.; Lazaro, C. (2020). Design of bending-active tied arches by using a multi-objective optimization method. Structures. 27:2319-2328. https://doi.org/10.1016/j.istruc.2020.07.045 ; S ; 2319 ; 2328 ; 27

2319 2328 27 ; S ; [EN] The design of bending-active structures is a challenging problem, due to the high non-linearity of the activation process, the coupling between member sizing, structural shape and the deformability and buckling sensitivity inherent in the resulting lightweight configurations. Due to the large number of form-finding variables, the choice of member sizing is one of the main difficulties at the conceptual phase. In this paper, authors propose a design tool to generate efficient structural configurations for braced bending-active tied arches using multi objective optimization strategies. Initially, a non-linear FE analysis is performed for each plausible configuration and at each generation of the optimization algorithm. In a second step, a genetic algorithm classifies the solutions and establishes new structural configurations according to best performance. Solutions are evaluated in terms of stresses in the active member and cables, and maximum deflections, as required by design codes for pedestrian bridges. Results are given in terms of non-dimensional parameters, in order to make them applicable to a wide variety of scales The authors gratefully acknowledge the financial support from the Spanish Ministry of Economy and Competitiveness through grant BIA2015-69330-P (MINECO), the European Union programme through grant ERASMUS Traineeships 2017 - E+ and the support from CALTER Ingenieria and SOFiSTiK AG for providing a software license Bessini, J.; Shepherd, P.; Monleón Cremades, S.; Lazaro, C. (2020). Design of bending-active tied arches by using a multi-objective optimization method. Structures. 27:2319-2328. https://doi.org/10.1016/j.istruc.2020.07.045

This article deals with the unified formulation of linear models for static elongated parts and in particular the class of models that include generalised shifts in addition to those required to define rigid solid movements of cross-sections. These models, called hyperviga models by authors, are characterised by the coupling between static and kinematic variables in the equilibrium equations. The article introduces pseudo-stress, new static variables representing the action of internal links controlling the change of shape of the transvesal section. The systematic procedure for assessing the distribution of voltages over cross-sections consistent with the hyperviga model, which approximates the voltage distribution corresponding to the three-dimensional elastic solution, is also developed. The system of unified formulation and its power for the construction of equations and for the assessment of the influence of the different parameters involved in the response are evident through its application to a problem that requires the introduction of additional degrees of freedom to those of rigid solids: the bending bending. Based solely on the kinematic of the cross-section expressed as a function of generalised displacements, using the proposed unified procedure, the variables, parameters and equations determining the response, as well as the expressions of the tensions in the section consistent with the formulation used, are obtained. Monleón Cremades, S.; Lazaro, C.; Casanova Colón, J.; Sunday Cape, A. (2015). Pseudostress and assessment of voltages in hyperviga models. International magazine of Numerical Methods for Engineering Calculation and Design. 31 (2): 71-80. doi:10.1016/j.rimni.2014.01.001 ; 71 80 31 2 ; This article deals with the unified formulation of linear models for static elongated parts and in particular the class of models that include generalised shifts in addition to those required to define rigid solid movements of cross-sections. These models, called hyperviga models by authors, are ...