1,721,031 research outputs found
Characterizing bifurcations and classes of motion in the transition to chaos through 3D-tori of a continuous experimental system in solid mechanics
No full textExperimental Tests in the Formulation of Reduced Order Analytical Models in the Planar Dynamics of Circular Arches
No full textThe role of the experimental analysis in the formulation of reduced order analytical models of planar arches under a vertical, sinusoidally varying, concentrated force on the tip is analyzed in this work. In particular, the use of the right analytical model able to reproduce the dynamics of arches having different sag to span ratio is discussed. After analyzing and discussing the non-linear analytical models available in the literature to study different families of arches, the minimal model able to reproduce the actual dynamics exhibited by experimental prototypes is considered. The experimental analysis conducted on two different models put into evidence the main phenomena of the forced dynamics and gives useful hints on the number and shape of the basis functions to be used in the analytical reduction. The main dynamical phenomenon exhibited by the arches is the loose of stability of the directly excited simple, I-mode, periodic solution and a complex bifurcation scenario towards different regular and non regular coupled motions where anti-symmetric components of the motion arise
The use of experimental tests in the formulation of analytical models for the finite forced dynamics of planar arches
No full textThe role of the experimental analysis in the formulation of reduced analytical models of planar arches under a vertical, sinusoidally varying, concentrated force on the tip is analyzed in this work. After recalling the theory describing the continuous problem for different initial geometries, using a standard Galerkin procedure, two ode's are derived and used to enlighten all the interesting phenomena exhibited by different prototypes tested in a companion experimental analysis whose results are also used to validate the shape functions used in the discretization procedure. The principal region of instability of the unimodal symmetric solution in which the nonlinear modal coupling excites antisymmetric components is studied analyzing the bifurcation conditions and the post-critical behavior
Post-critical finite, planar dynamics of a circular arch: Experimental and theoretical characterization of transitions to nonregular motions
No full textThe role of the experimental analysis in the formulation and validation of a reduced order analytical model of a planar arch under a vertical, sinusoidally varying, concentrated force on the tip, is analyzed in this work. One of the main dynamical phenomena exhibited by such systems is the loss of stability of the directly excited simple, 1-mode, symmetric, periodic solution and the evolution towards different regular and nonregular coupled motions where anti-symmetric components of the motion arise. The experimental analysis allows one to characterize the different classes of motion, bifurcation paths and main characteristics of the spatial flow and gives useful hints to be used in the analytical approximation. A minimal analytical model able to reproduce the actual dynamics of an experimental prototype is eventually proposed
Exploiting results of experimental nonlinear dynamics for reduced-order modeling of a suspended cable
No full textThe role of experimental nonlinear dynamics in the proper reduced-order modeling of an elastic suspended cable undergoing finite-amplitude vibrations is analyzed. Two main aspects of the problem are addressed, namely (i) the number of discretizing functions to be used in a low-order finite-degree-of-freedom theoretical model in order to detect the main features of the observed nonlinear regimes, and (ii) the capability of different orthonormal function bases employed in a specific reduced-order model to reproduce complex regimes and bifurcation scenarios. Based on results of in-depth experimental investigations of a quasiperiodic scenario to chaos in a cable/mass system, a three-degree-of-freedom model of suspended cable is formulated, and different truncated bases of approximating functions are considered. They include standard linear normal modes, and proper orthogonal modal functions obtained from variable sets of experimental proper orthogonal modes identified in different intervals of the frequency range wherein the quasiperiodic scenario develops. The performances of the ensuing discretized models and their capability to qualitatively detect some main features of the actual regular and nonregular experimental responses are investigated through computer simulations
Prove Dinamiche ed Ispezioni Visive in un Programma di Manutenzione di Ponti: il Caso della Provincia di TERAMO
No full text
Identification and condition assessment of the “Villa Passo” reinforced concrete arch bridge
No full text
- …
