The biodynamic response of the seated human body has been investigated with 20 males exposed to upward and downward shocks at 13 fundamental frequencies (1-16 Hz) and 18 magnitudes (up to ±8.3 ms-2). For 1- and 2- degree-of-freedom models, the stiffness and damping coefficients were obtained by fitting seat acceleration waveforms predicted from the measured force to the measured seat accelerati...

BACKGROUND Visco-elastic properties of the (neuro-)musculoskeletal system play a fundamental role in the control of posture and movement. Often, these properties are described and identified using stiffness-damping-inertia (KBI) models. In such an approach, perturbations are applied to the (neuro-)musculoskeletal system and subsequently KBI-model parameters are optimized to obtain a best fit be...

The contribution of foundation damping to offshore wind turbines (OWTs) is not well known, though researchers have back-calculated foundation damping from “rotor-stop” tests after estimating aerodynamic, hydrodynamic, and structural damping with numerical models. Because design guidelines do not currently recommend methods for determining foundation damping, it is typically neglected. This pape...

The contribution of foundation damping to offshore wind turbines (OWTs) is not well known, though researchers have back-calculated foundation damping from “rotor-stop” tests after estimating aerodynamic, hydrodynamic, and structural damping with numerical models. Because design guidelines do not currently recommend methods for determining foundation damping, it is typically neglected. This pape...

This paper presents a novel semi-active Variable Stiffness and Damping Isolator (VSDI) for vibration mitigation of structures. The proposed VSDI system consists of a traditional steel-rubber vibration absorber, as the passive fail-safe element, and a magneto-rheological elastomer (MRE) with a controllable (or variable) stiffness and damping behavior, as the passive-active element. MRE is a type...

A theoretical investigation into the prediction and measurement of squeeze film stiffness and damping for double hole entry hybrid journal bearings has been undertaken together with a review of previous work to identify critical bearing parameters. The analysis used a partial differentiation of the Poiseuille and Hagen-Poiseuille flow equations to develop a mathematical model for the bearing sq...

In this paper dynamic damping properties of a nominated flexible structural adhesive have been identified using an extended-direct modal based joint identification method. It has been revealed that damping characteristics of adhesive are correlated to both frequency and mode shape. Young’s and shear moduli increase with frequency but damping on the other hand, decrease. The results showed that ...

Concentrated suspensions of inclusions occur in asphalt and dental composite resins. Concentrated suspensions are also of use in achieving a combination of high stiffness and loss (the product E tan d ), desirable in damping layer and structural damping applications. For realizable particulate microstructures, analytical solutions for monodisperse inclusion morphologies such as spherical, rando...

A method of physical parameter system identification (SI) is proposed here for threedimensional (3D) building structures with in-plane rigid floors in which the stiffness and damping coefficients of each structural frame in the 3D building structure are identified from the measured floor horizontal accelerations. A batch processing least-squares estimation method for many discrete time domain m...

Hybrid micro-architected materials with unique combinations of high stiffness, high damping, and low density are presented. We demonstrate a scalable manufacturing process to fabricate hollow microlattices with a sandwich wall architecture comprising an elastomeric core and metallic skins. In this configuration, the metallic skins provide stiffness and strength, whereas the elastomeric core pro...