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Abstract: Previous studies of pounding responses of bridge structures to seismic loadings are usually based on the point to point pounding assumption by using the simplified lumped mass model or beam–column element model. It has been found these simplified models can be used to calculate bridge pounding response with consideration of only the longitudinal excitation. In a real bridge structure under seismic loading, pounding could take place along the entire or part of surfaces of the adjacent segments. Moreover, torsional response of the adjacent decks owing to the asymmetric deck or induced by spatially varying transverse ground motions at multiple bridge supports may result in eccentric poundings between adjacent bridge decks. A detailed 3D finite element model is necessary to consider the surface to surface and torsional response induced eccentric poundings and the corresponding damage. This paper performs numerical simulations of pounding damage between bridge girders and between bridge girder and the corresponding abutment of a two-span simply-supported bridge to spatially varying ground motions based on a detailed 3D finite element model by using the explicit finite element code LS-DYNA. The dislocation and unseating potentials of the bridge are also modelled. The bridge components including the bridge girders, abutments, pier, bearings, longitudinal reinforcement bars and stirrups are included in the model. The non-linear material behaviour including the strain rate effects of concrete and steel rebar are considered. The spatially varying ground motions are stochastically simulated. The damage mechanism of the bridge under spatially varying seismic loadings is examined. Numerical results show that the method adopted in the present paper can realistically capture the seismic induced damage of bridge structures. [Copyright &y& Elsevier]

In this paper, the buckling response of glass panels linearly supported along the top and bottom edges, under the action of in-plane shear loads, is investigated by means of analytical and Finite-Element (FE) methods. The typical buckling behaviour is first assessed in the hypothesis of fully neglecting the possible deformability contribution of adhesive linear supports, while successively the effects of linear, flexible sealant joints on the overall structural response of the same panels are also properly taken into account and highlighted. Based on extended parametric FE linear buckling and nonlinear incremental simulations, the influence of initial geometrical imperfections with various shapes and amplitudes, adhesive stiffnesses and glass types is investigated, both for monolithic and laminated glass panels. In the latter case, the accuracy of an equivalent thickness approach derived from early contributions is also demonstrated. Analytical approximating curves are proposed for the fitting of numerically derived buckling coefficients, so that they could represent a practical tool in the calculation of the expected Euler’s critical load. A normalized buckling curve for ideally simply supported glass panels under in-plane shear loads is finally recalled from past research projects and proposed as a rational design method for the examined loading and boundary condition. [ABSTRACT FROM AUTHOR]

Abstract: A new glass fibre reinforced polymer (GFRP) sandwich panel has been developed for flooring system. The new panel is made of modified phenolic core and E-CR glass skins. This paper presents the results of the experimental behaviour and the non-linear finite element analysis (FEA) of the GFRP sandwich panel. The experimental works investigate the behaviour of the GFRP sandwich panel, skin–core interaction, and core behaviour. A non-linear finite element model was developed to simulate the behaviour of the skin–core interaction, and the model was verified by comparing the results with those obtained from testing. The non-linear FE model was applied to a single span GFRP sandwich floor panel under point load test. The GFRP sandwich floor panel demonstrated a linear behaviour under point load. The results of the numerical simulations show a good agreement with the experimental results. [Copyright &y& Elsevier]

Abstract: This paper presents the second part of an experimental investigation carried out on a construction system based on completed in-situ sandwich panels with non-shear connectors, concerning the study of floor sandwich panels. Four-point flexural tests were carried out on several full-scale panel specimens with different slenderness ratios in order to study the behaviour of panels under vertical loads. Additionally, wall–floor nodes with different connection details were tested to analyze the effective degree of the rotational restraint of different realistic nodes. Furthermore, a loading test on the floor of a full scale 3D mock-up entirely built with sandwich panels was carried out to investigate the service and ultimate behaviour of a real floor. The most significant load-displacement diagrams for increasing load are illustrated and the failure modalities are discussed. The semi-composite behaviour of the panels, guaranteed by the internal layer of polystyrene and the reinforced concrete beams at the panel ends, is highlighted. The effects of the wall–floor connection and the bi-dimensional behaviour of the floor are also evaluated. Finally, some numerical simulations are performed with non-linear finite element models and some useful design indications are given. [Copyright &y& Elsevier]

Abstract: This paper deals with the shape generation of structural shells within the field of Conceptual Design. Both physical models and computational simulations are presented and discussed. The design is based on the biological principle of homeostasis which states the following: When an external agent attacks the structure, the latter defends itself “intelligently” to recover its bearing capacity. Here, heat is the external agent used to cause the model material degradation. Thus the model adopts a more appropriate structural shape in order to continue to resist loads. The physical experiment is carried out by introducing a Polymethyl Methacrylate (PMMA) plate in an oven with defined boundary conditions and loads. The virtual simulation is performed using a finite element software. A thermal elasto-plastic material model is included to represent the PMMA behavior. A comparison between the shapes found with both approaches is presented. Notwithstanding the diversity of the methods and uncertainties in the material characterization the match is more than acceptable. The numerical simulation may constitute a low cost complement to shell form-finding using the Homeostatic Model Technique. Additionally, the obtained shape is employed as the geometry of a structural shell and both, experimental and finite element stress analyses are performed, yielding a quasi-membranal behavior. [Copyright &y& Elsevier]