Investigation on Friction Features of Dissipative Lap Shear Connections by Means of Experimental and Numerical Tests
Mariana Zimbru1, Mario D’Aniello1, Attilio De Martino1, Massimo Latour2, *, Gianvittorio Rizzano2, Vincenzo Piluso2
Identifiers and Pagination:Year: 2018
Issue: Suppl-1, M9
First Page: 154
Last Page: 169
Publisher ID: TOBCTJ-12-154
Article History:Received Date: 01/10/2017
Revision Received Date: 01/11/2017
Acceptance Date: 10/01/2018
Electronic publication date: 23/05/2018
Collection year: 2018
open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Beam-to-column joints equipped with friction dampers are a viable solution to improve the dissipative capacity of moment Resisting Frames without any damage after severe seismic events. Recently, novel systems have been developed within the RFCS FREEDAM research project.
The objective of the work is to provide a rational selection based on engineering judgment, of possible materials to be used in friction dampers.
Both experimental analysis and Finite Element (FE) simulations have been carried out to assess the friction coefficients of several interfaces evaluating also their ability to withstand cyclic loading histories.
The experimental campaign showed that both hard and soft metals can be used in combination with stainless steel obtaining satisfactory performance under cyclic loads. In addition, at high slip velocities, large temperatures are developed within the specimen. Modelling this effect is crucial as it causes a reduction in the slip force capacity. This is due to the transverse dilatation that initially increases the pressure, while bolt tightening reduces due to elongation of the shank.
The experimental results, together with other similar data selected from technical literature, have been employed to validate FE models able to simulate the behaviour of lap shear friction connections, showing the influence of different modelling approaches over the simulated data. Subsequently, the validated model has been used to perform a set of simulations devoted to highlight the key parameters affecting the response of the lap shears and the possible strategies to improve the performance of the friction dampers.