نوع مقاله : یادداشت فنی
نویسندگان
دانشکده ی فنی و مهندسی عمران، دانشگاه سمنان
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
The basis of the modern design of earthquake resistant structures is based on
the structural ductility for absorption of earthquake energy and stability in large-scale displacement. Although metal materials are highly ductile, the Northridge earthquake showed that moment connections have a certain rotational
capacity under cyclic load, and severe earthquakes can lead to failure in the
area with low ductility. Therefore, in order to determine the level of actual
performance of structures under earthquake, such as the life safety or Collapse
Prevention, it is necessary to carry out more serious studies to determine the
final cyclic capacity of connections. On the other hand, after the collapse of
the Alfred P. Murrah Federal building, a truck explosion in 1995, as well as
the collapse of the World Trade Towers caused by the 2001 airplane
collapse;Determination of final capacity or failure of fittings under uniform
load; to investigate the structural behavior before the destruction or complete
destruction began. Since most of the tests carried out on the connections have
not been completed due to the limitations of the laboratory facilities and have
not been performed until the failure phase of the connection; hence, it does
not determine the final capacity of the connection. Mathematical studies are
also in the early stages due to the lack of reliable failure mechanism to
determine the time and how to start and spread the failure under monotonic and
cyclic loading. In this research,it has been attempted to be evaluated the
final capacity of the RBS connections under the monotonic and cyclic load .
Also, the place of the start of defect in this type of connection is evaluated.
In this regard, the final capacity of the reduced-sectional beam (RBS)
connections under uniform loading was determined using a column-removing
scenario with the SMCS model and the theory of growth and expansion of void
under uniform load. Then, the final capacity of the reduced-beam section (RBS)
connections under cyclic loading (SAC) was obtained by using the Cyclic Void
Growth Model (CVGM) and compared with the proposed final capacity of FEMA350 for RBS connection. The results of this study show that the cyclic rotational capacity of the RBS connections provided in FEMA350 is far more than actual. Also, the results show that the rotational capacity of the RBS connection under monotonic load is almost twice the amount given in FEMA350.
کلیدواژهها [English]