Experimental study on seismic behavior of high strength steel composite K-type eccentrically braced frames.

High strength steel composite K-type eccentrically braced frame is a new structural system, in which the link is made from steels with low yield strength and the others are made from high strength steel. In order to study the seismic behavior of such a structure, four one-bay one-story 1 : 2 scaled plane specimens were tested under the monotonic and cyclic load respectively. The failure modes and the main indexes of seismic behavior of specimens with various links length were analyzed. The results show that this new structural system is good at energy dissipation and ductility, and the way of energy absorbing by shear yielding is better than by flexural yielding. The ultimate displacement of monotonic test is greater than cyclic test, the bearing capacity of the former is higher than the latter, but the bearing capacity of the former is lower than the latter at the same displacement. In cyclic testing, the main failures were concentrated at links, while the other parts of the eccentrically braced frame keep in elastic status. This kind of structure is an excellent dual resistance system and easy to rehabilitate after earthquake. [ABSTRACT FROM AUTHOR]