Summary: | Slender precast concrete wall panels are currently in vogue for the
construction of tall single storey warehouse type buildings. Often their height to
thickness ratio exceed the present New Zealand design code (NZS 3101) limitations
of 30:1. Their real performance under earthquake attack is unknown. Therefore, this
study seeks to assess the dynamic performance of slender precast concrete wall panels
with different base connection details. Three base connections (two fixed base and
one rocking) from two wall specimens with height to thickness ratios of 60:1 were
tested under dynamic loading. The two fixed based walls had longitudinal steel
volumes of 1.27% to 0.54% and were tested on the University of Canterbury shaking
table to investigate their proneness to out-of-plane buckling. Based on an EUler-type
theoretical formula derived as part of the study, an explanation is made as to why
walls with high in-plane capacity are more prone to buckling. The theory was
validated against the present and past experimental evidence. The rocking base
connection designed and built in accordance with a damage avoidance philosophy
was tested on the shaking table in a similar fashion to the fixed base specimens.
Results show that in contrast with their fixed base counterparts, rocking walls can
indeed fulfil a damage-free design objective while also remaining stable under strong
earthquake ground shaking.
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