Articles 204 © Ernst & Sohn Verlag für Architektur und technische Wissenschaften GmbH & Co. KG, Berlin · Steel Construction 7 (2014), No. 3 DOI: 10.1002/stco.201410027 Structural glass corresponds to an innovative material with extraordinary aesthetical and architectonic potential that has undergone significant technological advances in recent years, yielding it stronger and safer. For this reason, the use of structural glass has increased considerably in the last decade and is now an unavoidable presence in most of recent reference buildings. The structural capacity of glass elements is brought in from reinforcing techniques of different types. One of the possibilities corresponds to pre stressed cables reinforcement. This technique is very effective in terms of resistance and deformability and corresponds to a light reinforcing element rendering the so called spider web effect. In the framework of the research project “S-Glass: Structural performance and design rules of glass beams externally reinforced” [1] study the behavior of laminated glass beams reinforced by too twin external steel rods. The work presented in the current paper is within the framework of S-Glass project aim- ing at characterizing the behavior of reinforced laminated glass beams in the non-crack regimen. For this purpose experimental and numerical analysis were prepared. The nu- merical model was used for a cable layout optimization analysis. Furthermore an analyti- cal solution is put forward, which tackles the beam-cable load transfer indetermination. Final conclusions are established on the bases of a comparison established between ex- perimental, numerical and analytical results. 1 Layout and geometry The layout of the structural model cor- responds to a four point bending test setup (Fig. 1). The beam is laterally re- strained at four diferent locations: the supports and near the load application positions. The structural system com- prises a twin set of cables with a diam- eter of 10 mm. The cables are external to the beam, shifting 0.05 m from the beam’s vertical mid plan. The lami- nated cross section is formed by two 10 mm annealed glass layers and a 1.52 mm SentryGlas ® Plus (SGP) film. 2 Finite element model The fnite element numerical model of the structure was prepared with soft- ware Abaqus [2]. The beam’s mesh comprises S4 square elements (Fig. 2). The compos- ite section option was used in order to model the contacts between glass and SGP. Truss fnite elements (T3D2) were used for the cables and solid f- nite elements (C3D8) were used for the rigid steel plates at the beam ends (see Fig. 2). Details on the numerical model can be found in [3]. 3 Optimization of the cable postion The objective is to determine the ideal position for the tension cable, which is the one leading to higher vertical forces with smaller forces in the cable. This will be achieved by an optimization based on the parameters “e” and “d” defning the layout of the cable (Fig. 3). Due to the fact that a pre stress force is present, the analysis was performed in two steps: Step 1: The pre-stress load in the ca- bles (Pe) is applied until 2/3 of the glass Behaviour of laminated glass beams reinforced with pre-stressed cables Sandra Jordão* Marco Pinho Luís Costa Neves João Pedro Martins Aldina Santiago Selected and reviewed by the Scientifc Committee of the 7th European Confer- ence on Steel and Composite Structures, 10 to 12 September 2014, Napoli, Italy * Corresponding author: sjordao@dec.uc.pt Fig. 1. Geometry and layout of the beam Fig. 2. Prototype a) and numerical model b) a) b)