Seismic Rehabilitation Design of Steel Moment Connection With Welded Haunch.
Seismic Rehabilitation Design of Steel Moment Connection
With Welded Haunch.
(223 K)
Yu, Q. S.; Uang, C. M.; Gross, J. L.
Journal of Structural Engineering, Vol. 126, No. 1,
69-78, January 2000.
Keywords:
steels; seismic rehabilitation; steel moment connection;
welded haunch; seismic performance; tensile stress; beam
theory
Abstract:
This paper describes a design procedure for the seismic
rehabilitation of pre-Northridge steel moment
connections using a welded haunch. Experimental results
from cyclic testing of full-scale specimens demonstrated
that welding a triangular haunch beneath the beam's
bottom flange significantly improved the seismic
performance of steel moment connections. The welded
haunch drastically changed the beam shear force transfer
mechanism, which assisted in reducing the demands at the
beam flange groove welds. Analytical studies further
showed that the tensile stress in the existing beam
flange groove weld can be reduced to a reasonable level
if the flange of the haunch is designed to provide
sufficient stiffness and strength. However, traditional
beam theory cannot provide a reliable prediction of the
beam's flexural stress distribution near the column
face. A simplified model that allows the designer to
predict the stress level in the beam flange groove welds
is presented.
Building and Fire Research Laboratory
National Institute of Standards and Technology
Gaithersburg, MD 20899