| Testing
of concrete walls and columns subjected to axial compression shows that
double head studs used as cross ties are more effective than conventional
stirrups with 90 and 180 degree hooks in confining the concrete, thus
improving strength and ductility. Unlike conventional stirrups, the studs
with heads sufficiently large enough to develop yield strength do not
require hooks and bends which must engage the longitudinal bars. It is
proposed that because of the superiority of studs in increasing strength
and ductility of columns and walls, design codes should allow reduced
cross-sectional areas and/or larger spacing when studs are used as cross
ties. |
