Assessment of Scale Effects in the Experimental Evaluation of the Coefficient of Friction of Sliding Isolators

Abstract

Sliding bearings have been extensively used to implement base isolation design in civil engineering works. Testing of isolators is conducted for characterizing the design properties to be used in structural analysis, as well as for verifying the performance of the devices before their application. The quantification of the effects of scaling specimens and testing on the observed coefficient of friction is an issue, due to the nonlinear dependence of the latter on several factors like load, velocity and temperature. An effort to quantify such effects is pursued in the study. The coefficient of friction is parameterized as a function of few dimensionless quantities related to heating of the sliding surfaces, and similarity conditions are assessed under which the influence of scaling is below normal production variability.

Emerging superelastic SMA core damping elements for seismic application

“…Scaled specimens are expected to provide different responses in comparison to their full-scale counterparts, and this needs special attention. The reasons for the scale effect of SMA elements include inconsistent manufacturing and annealing strategy for different SMA elements, which are different from conventional dampers, e.g., Quaglini et al (2022). 4) Temperature effect.…”

Seismic Response Mitigation of Base-Isolated Buildings

“…Since these fragility curves represent uncertainty in ground motion intensity and frequency content, while the structure is assumed to be deterministic, the resulting fragility curves are called as simplified fragility curves in the sense that they might be different from real fragilities of a structure with uncertain parameters. There is future scope for experimental verification of the concept like reference [45]. The TMD schemes reduce the probability of the considered damage state by about 10% across a range of PGA.…”

Discussion of Stick-Slip Dynamics of 2DOF Sliding Systems Based on Dynamic Vibration Absorbers Analysis

“…In addition, stick-slip is observed in many industrial products, including automotive parts such as disc brakes and clutches [5,6]. Other examples of stick-slip occurrences that should be prevented are, for example, vibration isolators installed in structures [7][8][9]. A historical review of stick-slip phenomena and its analysis is provided by Feeny et al [10].…”