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A constitutive model is developed to efficiently capture the nonlinear hysteretic properties of a new type of high-damping metal wire mesh (HDMWM). In the HDMWM, the metal wire mesh is woven with multi-strand twisted wires in a certain regularity. In the quasi-static test, six batches of metal wire mesh (MWM) and HDMWM specimens with different densities and varying number of strands are prepared and their mechanical properties are characterized by secant stiffness, energy consumption and loss factor. Results show that for the same density, the energy consumption and loss factor of HDMWM specimens are higher than MWM specimens by 10.69 ~ 22.83% and 44.19 ~ 48.44%, respectively. Additionally, HDMWM is found to have a higher damping level than MWM. A constitutive model is proposed that comprises a cantilever beam as the force analysis element where the change of the arc angle of the element mesh is similar to a normal distribution. The accuracy of the model is verified by error analysis, which shows that the relative percentage error between model results and test results is 0.97 ~ 12.13%. Therefore, the constitutive model can reflect the mechanical properties of HDMWM with reasonable accuracy. [ABSTRACT FROM AUTHOR]

This work presents the experimental characterization and improved model of multi-strand entangled metallic wire materials (MS-EMWMs). MS-EMWM is a novel damping material made of several strands of entangled wires using a modified manufacturing process. Six batches of specimens were fabricated and tested under quasi-static loading. Secant stiffness and loss factor were calculated to indicate the mechanical properties. The results showed that MS-EMWM has the characteristics of high damping energy dissipation compared to EMWM. A micro-multi-strand spiral spring model was proposed to predict the mechanical properties of MS-EMWM. The probability distribution of micro-spring pairs between wires was used to characterize the random combination of materials. According to the results, the improved model can effectively reflect the mechanical behavior of MS-EMWM. The mechanical properties of MS-EMWM were predicted by the coefficient matrix obtained by particle swarm optimization. Through the prediction and test results, the predicted results are acceptable. [ABSTRACT FROM AUTHOR]

In this paper, a symmetrically coated damping structure for entangled metallic wire materials (EMWM) of pipelines was designed to reduce the vibration of high temperature (300 °C) pipeline. A series of energy dissipation tests were carried out on the symmetrically coated damping structure at 20–300 °C. Based on the energy dissipation test results, the hysteresis loop was drawn. The effects of temperature, vibration amplitude, frequency, and density of EMWM on the energy dissipation characteristics of coated damping structures were investigated. A nonlinear energy dissipation model of the symmetrically coated damping structure with temperature parameters was established through the accurate decomposition of the hysteresis loop. The parameters of the nonlinear model were identified by the least square method. The energy dissipation test results show that the symmetrically coated damping structure for EMWM of pipelines had excellent and stable damping properties, and the established model could well describe the changing law of the restoring force and displacement of the symmetrically coated damping structure with amplitude, frequency, density, and ambient temperature. It is possible to reduce the vibration of pipelines in a wider temperature range by replacing different metal wires. [ABSTRACT FROM AUTHOR]