Dynamic beam-end tests: Investigation using split Hopkinson bar

Publikation: Beitrag in FachzeitschriftForschungsartikelBeigetragenBegutachtung

Beitragende

Abstract

The bond between concrete and steel reinforcement is a highly investigated topic under both quasi-static and dynamic loading conditions. Strain rate sensitivity and dynamic increase factor are the key aspects affecting the resulting response of the structure and represent crucial parameters for modelling the impact-related events. Measuring the bond properties under dynamic conditions, however, is a complex task requiring advanced experimental techniques and methodology. In this paper, the bond stress-slip relationships during dynamic pull-out was measured using an innovative technique based on a tensile split Hopkinson bar and a near-to-full-scale beam-end specimen representing an end-part of a reinforced concrete beam.

A tensile split Hopkinson bar was used to generate a tensile stress wave with a long duration that pulls a reinforcement bar with a short bond length out of the concrete block. As a very complex wave propagation behavior was observed during the impact, the forward and backward propagating waves have to be separated and subsequently used to properly calculate the bond stress-slip relationship. Two redundant methods utilizing strain gauge signals and digital image correlation for separation of the longitudinal stress waves were employed to solve the problem. The proof-of-concept and applicability of the method which are the main focus of the contribution were demonstrated with a numerical simulation performed in LS-DYNA. An exemplary evaluation of the results of the real tests performed at medium impact velocity with full pull-out of the rebar was performed. The presented method is considered suitable for the evaluation of the dynamic bond stress-slip relationship and produced high-quality results during the initial impact phase and reasonable quality results up to the full pull-out.
Titel in Übersetzung
Dynamische Beam-End Versuche: Untersuchungen mit dem Split-Hopkinson-Bar

Details

OriginalspracheEnglisch
Aufsatznummer104417
FachzeitschriftInternational Journal of Impact Engineering
Jahrgang172
PublikationsstatusVeröffentlicht - 26 Okt. 2022
Peer-Review-StatusJa

Externe IDs

unpaywall 10.1016/j.ijimpeng.2022.104417
Scopus 85141913703
ORCID /0000-0003-0398-2735/work/141543511
ORCID /0000-0002-9490-606X/work/142250004
ORCID /0000-0002-1596-7164/work/142255665

Schlagworte

Schlagwörter

  • Beam-end test, Digital image correlation, Dynamic bond stress-slip relationship, Dynamic pull-out, LS-DYNA, Tensile split Hopkinson bar, Wave separation