Civil and Environmental Engineering, Imperial College London
Doi
Abstract
The use of tubular columns in conjunction with reinforced concrete
flat slabs provides structurally
efficient solutions which avoid undesirable failure modes such as those associated with
shear. This thesis is concerned with the development of a tubular column-to-
flat slab connection
system that enables reliable performance under seismic loading conditions. During this
research a novel detail which features a gap around the column is proposed and developed;
hence only the structural steel shearhead establishes the connection. The exposed parts of
the shear arms (fuses) are designed to yield prior to punching shear failure, in a way that
utilises the favourable features of steel in terms of the response to seismically induced loads.
The proposed connection could serve as a primary lateral resisting system within all building
configurations in regions of low to moderate seismicity or as a secondary system in areas of
signi cant seismicity. In order to provide validation for the proposed details as well as associated
numerical and design procedures, a purpose-built rig which is suitable for large scale
testing of structural sub assemblages under combined gravity and uniaxial lateral loading,
has been designed and constructed, and subsequently employed for a number of tests. Test
results and numerical analyses are presented with respect to a conventional con guration,
as well as for the proposed, partially embedded connection. The latter is shown to offer
enhanced ductility compared with traditional forms. The results are used to demonstrate the
favourable inelastic performance of the proposed detail in terms of ductility, low degradation
effects and increased energy dissipation capabilities. Complementary small scale slab panel
tests are also used to further optimise the composite behaviour of the proposed detail. Additionally,
a closed form solution based on plastic limit analysis which can serve as a basis for
a simplified design approach is proposed. Finally, the main findings from the experimental
and analytical investigations are highlighted, and recommendations for future research are
outlined