SEISMIC BEHAVIOUR OF HIGH-PERFORMANCE FIBRE REINFORCED CONCRETE (HPFRC) LOW-RISE WALLS WITH SIMPLIFIED REINFORCEMENT DETAILING

The use of tensile strain-hardening, High-Performance Fibre Reinforced Concrete (HPFRC) in low-rise structural walls was experimentally evaluated as a means to simplify reinforcement detailing without compromising wall seismic behaviour in terms of drift capacity and shear strength. Results from five HPFRC low-rise wall specimens with shear span-to-wall length ratio of either 1.2 or 1.5 are reported. The walls were reinforced with either hooked steel fibres or ultrahigh molecular weight polyethylene (Spectra) fibres in a 1.5% or 2.0% volume fraction and subjected to earthquake-induced displacement reversals with maximum shear stress demands ranging from 0.39√fc′ to 0.74√fc′ MPa. Little or no confinement reinforcement was used in the wall boundary regions and the web distributed reinforcement was reduced compared to that required in the 2008 ACI Building Code. The tests reported herein confirmed that HPFRC materials can reliably confine the boundary region of low-rise walls and ensure a stable hysteresis behaviour. The HPFRC walls developed a dense array of diagonal and flexural cracks and sustained drifts ranging between 2.1% and 3.0%. Only minor shear-related damage was observed at drifts below 1.3% and concrete spalling, if any, was not substantial even at drifts as large as 2.0%. In terms of shear distortion, 0.015 rad represented a conservative limit for the shear distortion capacity of the HPFRC wall specimens. The wall-foundation interface was found to be particularly critical in HPFRC low-rise walls because no fibres bridge that section, making it susceptible to reinforcement yielding localization and potential sliding shear failure. The use of dowel reinforcement to strengthen the cold joint and force inelastic deformations to occur within the HPFRC wall was found to be effective to prevent a premature sliding shear failure.

ATHANASOPOULOU Adamantia;  PARRA-MONTESINOS Gustavo;  KIM Kwang-Yeon; 

2013-03-18

RILEM Publications S.A.R.L

JRC70980

978-2-35158-132-2 (print),    978-2-35158-133-9 (online),   

https://publications.jrc.ec.europa.eu/repository/handle/JRC70980,