PSI - Issue 13

Uroš Tatić et al. / Procedia Structural Integrity 13 (2018) 496– 502 Author name / Structural Integrity Procedia 00 (2018) 000–000

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5.3. Results Main effort was focused on determining the displacement on the mullion profile during the simulation. Numerical results of performed simulations of a model 1 are presented on Fig. 5 (left). During the development of the Model 2 simulation main effort was focused on determining contact behaviour between individual wood elements connected with the use of the dowels. Numerical results of performed simulations are presented on Fig. 5 (right). 6. Discussion Performed simulations of model 1 showed significant inconsistencies (test value for displacement of 45 mm; numerical value of displacement 11 of mm). During the analyzing process it was determined that the tie constrain used to mutually restrain individual parts does not provide adequate behavior of the global model. Isotropic behavior of the wood also significantly influenced stiffness of model. Performed Simulations on model 2 shown significant reduction of the inconsistencies presented in the Model 1. During the analyzing process it was determined that the contact between window elements (connection with use of dowels) allows rotation. Numerical simulations were performed with different options defined to prevent rotation. Solution with the best relation between applicability and results proposed new design where a mullion would go through bottom and top beam, and dowels would be positioned in a way to restrain rotation. New design proposes inverted connection of the middle element and the top and bottom as seen in Figure 7. Middle beam was design to go from bottom to the top, whereas the top and bottom profile would be connected to it. 7. Conclusion Performed simulation proven that the contact between individual wooden window elements represent the weakest point of the design. Development of the numerical model has shown that orthotropic behaviour of the wood, as well as the connections between mutual elements have a major roll on the behaviour of the model. Rotation of the mullion at the contact point was determined. New solutions used to restrain the motion with minimal modifications in the production process was determined. Experimental analyses of the new proposed design are to be done in the future in order to determine the behaviour of the new design. Combination of the experimental setup and the numerical simulations provided insight in to the behaviour on the local level which was overseen in previous development process. New proposed design provides significant improvement over the traditional dowel constrain, but in order to define standard criteria a mullion reinforcement must be insured. Small inconsistencies in the longitudinal modulus of the elasticity were noticed and are to be evaluated in the future work. Acknowledgements The authors would like to acknowledge the support of European Commission in the scope of Horizon 2020 project XtremelY (739524), Slovenian Ministry of Education, Science and Sport, and European Regional Development Fund in the scope of project TIGR4smart. References C. E. Ochoa, M. B. C. Aries, E. J. van Loenen, and J. L. M. Hensen, “Considerations on design optimization criteria for windows providing low energy consumption and high visual comfort,” Applied Energy , vol. 95, pp. 238–245, Jul. 2012. SIST EN 12210:2000 - Windows and doors - Resistance to wind load – Classification May 2000 Fig. 6 Existing connection design (left); Proposed inverted connection design solution (right)