R. Masiani | Università degli Studi "La Sapienza" di Roma (original) (raw)
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Papers by R. Masiani
Computational Mechanics
Mechanical behaviour of particle composite materials is growing of interest to engineering applic... more Mechanical behaviour of particle composite materials is growing of interest to engineering applications. A computational homogenization procedure in conjunction with a statistical approach have been successfully adopted for the definition of the Representative Volume Element (RVE) size, that in random media is an unknown of the problem, and of the related equivalent elastic moduli. Drawback of such a statistical approach to homogenization is the high computational cost, which prevents the possibility to perform series of parametric analyses. In this work, we
Computational Mechanics
Mechanical behaviour of particle composite materials is growing of interest to engineering applic... more Mechanical behaviour of particle composite materials is growing of interest to engineering applications. A computational homogenization procedure in conjunction with a statistical approach have been successfully adopted for the definition of the Representative Volume Element (RVE) size, that in random media is an unknown of the problem, and of the related equivalent elastic moduli. Drawback of such a statistical approach to homogenization is the high computational cost, which prevents the possibility to perform series of parametric analyses. In this work, we
International Journal of Solids and Structures, 1999
Some aspects concerning the identification of continuum coarse models from fine discrete models a... more Some aspects concerning the identification of continuum coarse models from fine discrete models are discussed. The preservation of the mechanical power, in the transition from the microscopic to the macroscopic description, is required. A procedure based on the equivalence ofthe virtual power provides a natural way to select the continuum satisfying this requirement. Having the advantages of an integrai procedure, it gives good results if the coarse model is a multifield continuum with strain fields compatible with those of the fine model. In this situation both models share the same material symmetry group. This is shown with reference to rigid particle systems. In particular, the symmetry group of the discrete material is defined and its transformation into that of an equivalent micropolar continuum is studied in detail. Numerical analyses are also performed to investigate the effect of change in the material symmetries.
This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free... more This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free rocking. Aim of the laboratory campaign is the estimation of kinetic energy damping exhibited by walls released with non-zero initial conditions of motion. Such energy damping is necessary for dynamic modelling of unreinforced masonry local mechanisms. After a brief review of the literature on this topic, the
The response of two-degree-of-freedom chain systems with elements which have hysteretic restoring... more The response of two-degree-of-freedom chain systems with elements which have hysteretic restoring force, is studied under sinusoidal imposed motion. The hysteretic behavior of the elements are described by the Masing model. Since attention is focused on the periodic response, the multi-component harmonic balance method is used to evaluate the solution. This method, combined with a path-following algorithm, is a robust tool capable of accurately describing the frequency response curves, which are particularly complex in some frequency range due to the strong non-linearities and non-linear modal coupling. The in uence of hysteretic law parameters is investigated, and, in particular, the ratio between the two natural frequencies.
Computational Stochastic Mechanics, 1991
Computational Mechanics
Mechanical behaviour of particle composite materials is growing of interest to engineering applic... more Mechanical behaviour of particle composite materials is growing of interest to engineering applications. A computational homogenization procedure in conjunction with a statistical approach have been successfully adopted for the definition of the Representative Volume Element (RVE) size, that in random media is an unknown of the problem, and of the related equivalent elastic moduli. Drawback of such a statistical approach to homogenization is the high computational cost, which prevents the possibility to perform series of parametric analyses. In this work, we
Computational Mechanics
Mechanical behaviour of particle composite materials is growing of interest to engineering applic... more Mechanical behaviour of particle composite materials is growing of interest to engineering applications. A computational homogenization procedure in conjunction with a statistical approach have been successfully adopted for the definition of the Representative Volume Element (RVE) size, that in random media is an unknown of the problem, and of the related equivalent elastic moduli. Drawback of such a statistical approach to homogenization is the high computational cost, which prevents the possibility to perform series of parametric analyses. In this work, we
International Journal of Solids and Structures, 1999
Some aspects concerning the identification of continuum coarse models from fine discrete models a... more Some aspects concerning the identification of continuum coarse models from fine discrete models are discussed. The preservation of the mechanical power, in the transition from the microscopic to the macroscopic description, is required. A procedure based on the equivalence ofthe virtual power provides a natural way to select the continuum satisfying this requirement. Having the advantages of an integrai procedure, it gives good results if the coarse model is a multifield continuum with strain fields compatible with those of the fine model. In this situation both models share the same material symmetry group. This is shown with reference to rigid particle systems. In particular, the symmetry group of the discrete material is defined and its transformation into that of an equivalent micropolar continuum is studied in detail. Numerical analyses are also performed to investigate the effect of change in the material symmetries.
This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free... more This paper presents an ongoing experimental program on unreinforced masonry walls undergoing free rocking. Aim of the laboratory campaign is the estimation of kinetic energy damping exhibited by walls released with non-zero initial conditions of motion. Such energy damping is necessary for dynamic modelling of unreinforced masonry local mechanisms. After a brief review of the literature on this topic, the
The response of two-degree-of-freedom chain systems with elements which have hysteretic restoring... more The response of two-degree-of-freedom chain systems with elements which have hysteretic restoring force, is studied under sinusoidal imposed motion. The hysteretic behavior of the elements are described by the Masing model. Since attention is focused on the periodic response, the multi-component harmonic balance method is used to evaluate the solution. This method, combined with a path-following algorithm, is a robust tool capable of accurately describing the frequency response curves, which are particularly complex in some frequency range due to the strong non-linearities and non-linear modal coupling. The in uence of hysteretic law parameters is investigated, and, in particular, the ratio between the two natural frequencies.
Computational Stochastic Mechanics, 1991