Title: Cyclic Behavior of Expanded Slate Lightweight Self-Consolidating Concrete Beam-Column Joints Containing Polyvinyl Alcohol Fibers

Author(s): Ahmed T. Omar, Basem H. AbdelAleem, Assem A. A. Hassan

Publication: Materials Journal

Volume:

Issue:

Appears on pages(s):

Keywords: beam-column joints; cyclic loading; ductility; energy dissipation; lightweight Stalite aggregate; polymeric fibers; stiffness degradation

DOI: 10.14359/51740773

Date: 5/1/2024

Abstract:
This paper investigates the structural performance of lightweight self-consolidating concrete (LWSCC) and lightweight vibrated concrete (LWVC) beam-column joints reinforced with mono-filament polyvinyl alcohol (PVA) fibers under quasi-static reversed cyclic loading. A total of eight exterior beam-column joints with different lightweight aggregate types (coarse and fine expanded slate aggregates), different PVA fiber lengths (8-12 mm [0.315-0.472 in.]), and different percentages of fiber (0.3% and 1%) were cast and tested. The structural performance of the tested joints was assessed in terms of failure mode, hysteretic response, stiffness degradation, ductility, brittleness index, and energy dissipation capacity. The results revealed that LWSCC specimens made with expanded slate fine aggregates (LF) appeared to have better structural performance under reversed cyclic load compared to specimens containing expanded slate coarse aggregates (LC). Shortening the length of PVA fibers enhanced the structural performance of LWSCC beam-column joints (BCJs) in terms of initial stiffness, load-carrying capacity, ductility, cracking activity, and energy dissipation capacity compared to longer fibers. The results also indicated that using an optimized LWVC mixture with 1% PVA8 fibers and a high LC/LF aggregate ratio helped to develop joints with significantly enhanced load-carrying capacity, ductility, and energy dissipation while maintaining reduced self-weight of 28% lower than normal-weight concrete.