https://sam.ensam.eu:443 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Sun, 15 Mar 2026 04:56:05 GMT 2026-03-15T04:56:05Z http://hdl.handle.net/10985/8231 Conception et validation d’une liaison boulonnée dissipative HAMMAMI, Chaima; BALMES, Etienne; GUSKOV, Mikhail On présente ici une méthodologie de conception d’une liaison boulonnée dissipative ainsi que sa validation par une étude expérimentale. Un premier calcul statique permet de caractériser la zone de compression induite à l’interface par le serrage. Cette zone contribue seule à la tenue statique de la liaison et est conservée en liaison métallique. On justifie ensuite l’intérêt d’introduire une couche de matériau viscoélastique dans le reste de la surface de contact. La réalisation expérimentale permet de montrer des augmentations d’amortissement d’un facteur supérieur à trois pour les modes globaux et illustre les difficulités liées aux défauts de forme des surface de contact. On montre enfin comment les performances peuvent être optimisées numériquement. Tue, 01 Jan 2013 00:00:00 GMT http://hdl.handle.net/10985/8231 2013-01-01T00:00:00Z HAMMAMI, Chaima BALMES, Etienne GUSKOV, Mikhail On présente ici une méthodologie de conception d’une liaison boulonnée dissipative ainsi que sa validation par une étude expérimentale. Un premier calcul statique permet de caractériser la zone de compression induite à l’interface par le serrage. Cette zone contribue seule à la tenue statique de la liaison et est conservée en liaison métallique. On justifie ensuite l’intérêt d’introduire une couche de matériau viscoélastique dans le reste de la surface de contact. La réalisation expérimentale permet de montrer des augmentations d’amortissement d’un facteur supérieur à trois pour les modes globaux et illustre les difficulités liées aux défauts de forme des surface de contact. On montre enfin comment les performances peuvent être optimisées numériquement. http://hdl.handle.net/10985/8593 Meta-models of repeated dissipative joints for damping design phase HAMMAMI, Chaima; BALMES, Etienne Developing tools to predict dissipation in mechanical assemblies starting from the design process is a subject of increasing interest. Design phases imply numerous computations resulting from the use of families of models with varying properties. Model reduction is thus a critical tool to make such design studies affordable. Existing model reduction methods make computation of models with detailed non-linear parts accessible although costly although allowing the generation of a small size model for the linear part. One is, thus, interested in introducing meta-models of the behavior in the non-linear part by determining a basis of principal joint deformations. In this work, one seeks to validate the ability to predict macro-forces associated with the principal deformation shapes. Taking the case of aeronautic structures as cylindrical ones with multiple joints, one seeks to validate the construction of a meta-model associated to the joint. The ability to use such a meta-model to predict damping associated with viscoelastic behavior in a specifically designed bolted joint will be illustrated. Wed, 01 Jan 2014 00:00:00 GMT http://hdl.handle.net/10985/8593 2014-01-01T00:00:00Z HAMMAMI, Chaima BALMES, Etienne Developing tools to predict dissipation in mechanical assemblies starting from the design process is a subject of increasing interest. Design phases imply numerous computations resulting from the use of families of models with varying properties. Model reduction is thus a critical tool to make such design studies affordable. Existing model reduction methods make computation of models with detailed non-linear parts accessible although costly although allowing the generation of a small size model for the linear part. One is, thus, interested in introducing meta-models of the behavior in the non-linear part by determining a basis of principal joint deformations. In this work, one seeks to validate the ability to predict macro-forces associated with the principal deformation shapes. Taking the case of aeronautic structures as cylindrical ones with multiple joints, one seeks to validate the construction of a meta-model associated to the joint. The ability to use such a meta-model to predict damping associated with viscoelastic behavior in a specifically designed bolted joint will be illustrated. http://hdl.handle.net/10985/8597 Reduced joint models for damping design of multi-jointed structures HAMMAMI, Chaima; BALMES, Etienne; GUSKOV, Mikhail − Design of damping in multi-jointed structures is studied here. − Dissipation sources are viscoelastic behavior and contact/friction at joints interfaces. − Reduction on meta-models of nonlinear joints models is investigated. − Experimental characterization of nonlinear forces. Wed, 01 Jan 2014 00:00:00 GMT http://hdl.handle.net/10985/8597 2014-01-01T00:00:00Z HAMMAMI, Chaima BALMES, Etienne GUSKOV, Mikhail − Design of damping in multi-jointed structures is studied here. − Dissipation sources are viscoelastic behavior and contact/friction at joints interfaces. − Reduction on meta-models of nonlinear joints models is investigated. − Experimental characterization of nonlinear forces. http://hdl.handle.net/10985/10455 Numerical design and test on an assembled structure of a bolted joint with viscoelastic damping HAMMAMI, Chaima; BALMES, Etienne; GUSKOV, Mikhail Mechanical assemblies are subjected to many dynamic loads and modifications are often needed to achieve acceptable vibration levels. While modifications on mass and stiffness are well mastered, damping modifications are still considered difficult to design. The paper presents a case study on the design of a bolted connection containing a viscoelastic damping layer. The notion of junction coupling level is introduced to ensure that sufficient energy is present in the joints to allow damping. Static performance is then addressed and it is shown that localization of metallic contact can be used to meet objectives, while allowing the presence of viscoelastic materials. Numerical prediction of damping then illustrates difficulties in optimizing for robustness. Modal test results of three configurations of an assembled structure, inspired by aeronautic fuselages, are then compared to analyze the performance of the design. While validity of the approach is confirmed, the effect of geometric imperfections is shown and stresses the need for robust design. Thu, 01 Jan 2015 00:00:00 GMT http://hdl.handle.net/10985/10455 2015-01-01T00:00:00Z HAMMAMI, Chaima BALMES, Etienne GUSKOV, Mikhail Mechanical assemblies are subjected to many dynamic loads and modifications are often needed to achieve acceptable vibration levels. While modifications on mass and stiffness are well mastered, damping modifications are still considered difficult to design. The paper presents a case study on the design of a bolted connection containing a viscoelastic damping layer. The notion of junction coupling level is introduced to ensure that sufficient energy is present in the joints to allow damping. Static performance is then addressed and it is shown that localization of metallic contact can be used to meet objectives, while allowing the presence of viscoelastic materials. Numerical prediction of damping then illustrates difficulties in optimizing for robustness. Modal test results of three configurations of an assembled structure, inspired by aeronautic fuselages, are then compared to analyze the performance of the design. While validity of the approach is confirmed, the effect of geometric imperfections is shown and stresses the need for robust design.