Haunch Retrofitting of Exterior Beam-Column Connection

Abstract

Three beam-column joints sub-assemblies of 1/3 rd reduced scale was tested under monotonic loading conditions. The beam-column connections were comprised of one control model having low concrete strength and having no joint ties, another similar model with diagonal hooks in the joint, and a retrofitted model using energy dissipating haunch. Haunch retrofitting of the deficient model was done to shift the damage from joint to beam and was connected through external anchors to avoid anchors failure. The haunch retrofitting substantially increased the strength of the model with some cracking/damage shift towards the beam but damage in the joint could not be prevented due to delayed action of the haunch that was due to lose attachment of the anchors.

In-Plane Quasi-Static Cyclic Testing of Rc Frames Retrofitted With Rigid/Dissipating Steel Haunches

“…The recent damaging earthquakes have raised concerns among designers regarding the economically viable repair or demolition and reconstruction of earthquake-damaged reinforced concrete frames. Research is needed to determine whether strengthening existing RC frames with haunches that have weaker beamcolumn joints can improve seismic performance [7][8][9][10][11][12][13][14][26][27][28][29][30][31][32][33][34]. It may also be useful in restoring and potentially strengthening the seismic resistance of seismically damaged RC frames with weaker beamcolumn joints.…”