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Showing 1 to 8 of 8 for “"Acoustoelastic"”.
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Acoustoelastic effects of surface waves in concrete subjected to compressive and bending stresses
This investigation focuses on the study of acoustoelastic effects on Rayleigh surface waves (R-waves) in concrete samples subjected to 4-point load bending and uniaxial compression, considering a broad range of strain levels. The main objectives are (1) to study individually the acoustoelastic …
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ΣΥΜΒΟΛΗ ΣΤΗΝ ΑΝΑΛΥΣΗ ΚΑΙ ΣΤΟΝ ΥΠΟΛΟΓΙΣΜΟ ΑΚΟΥΣΤΙΚΟΕΛΑΣΤΙΚΩΝ ΦΑΙΝΟΜΕΝΩΝ
THE ACOUSTOELASTIC PHENOMENA ARE A CLASS OF FLUID-STRUCTURE INTERACTION PHENOMENA, WITH SPECIAL IMPORTANCE TO THE OVERALL SPECTRUM OF THE ABOVE PHENOMENA. THIS FACT IS DEVELOPED EXTENSIVELY IN PART 1 OF THE THESIS, WHERE A REVIEW IS ATTEMPTED OF ALL THE PHYSICAL FLUID-STRUCTURE INTERACTION …
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Modeling and Experimental Analysis of Piezoelectric Augmented Systems for Structural Health and Stress Monitoring Applications
… with focus being cast on impedance-based SHM and acoustoelastic-based stress measurement techniques. While impedance-based SHM has been successfully implemented as a damage detection technique, the utilization of electromechanical impedance measurements for damage characterization imposes several …
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Modeling nonlinear material behavior at the nano and macro scales
… nano and macro scales. These methods include, acoustoelastic theory, molecular dynamics and finite element models. The nonlinear indentation response of Ni thin films of thicknesses in the nano scale was studied using molecular dynamics simulations with embedded atom method (EAM) interatomic …
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Ultrasonic stress measurement for evaluating the adequacy of gusset plates
… of gusset plates. This research utilizes the acoustoelastic effect to evaluate actual stress levels by assessing the acoustic birefringence in a steel material. The birefringence measurement evaluates normalized variations of polarized shear waves propagating through the plate thickness, which …
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Analysis and Experimental Investigation of Wave Propagation and Energy Transfer in Mechanical Rotator Metamaterials
… a stretchable rotator lattice capable of extreme acoustoelastic effects for reconfigurable directivity, refraction steering, on-demand signal time delay, and parametric amplification. Additionally, closed-form perturbation analyses are introduced for two specific cases: nonlinear evanescent waves …
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Investigation of Linear and Nonlinear Torsional Guided Waves in Hollow Circular Cylinders for Damage Detection
… and single frequency. On the other hand, acoustoelastic effect is studied in Chapter 5. A series of case studies are carried out to observe the group velocity change with respect to different levels of loading. The nonlinear features, such as combinational harmonics and second harmonics, …
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Reduced order models for fluid-structure interaction systems by mixed finite element formulation
… finite element formulations are introduced for acoustoelastic fluid- structure interaction (FSI) systems. For acoustic fluid, in addition to displacement- pressure (u/p) mixed formulation, a three-field formulation, namely, displacement-pressure-vorticity moment formulation (u - p -[Lambda]) is …