Prequalified Connections for Special and Intermediate Steel Moment Frames for Seismic Applications, ANSI/AISC 358-05

摘要: Building code provisions for the seismic resistant design of structures incorporate two basic types requirements. The first these is very similar to requirements most other loading and comprises specification minimum permissible strength structural stiffness. second unique resistance consists prescriptive criteria on detailing practice elements. While stiffness have been part building codes nearly 100 years, requirements, which include such things as prescription volumetric ratio spacing reinforcing in concrete structures, width/thickness ratios elements members steel are a recent addition code. They were introduced into late 1960s primarily affected reinforced structures. However, researchers continued understand importance performance actual earthquakes made clear profession that poor directly leads adverse behavior, volume complexity has steadily increased. Extensive following 1971 San Fernando earthquake. Requirements timber masonry also added throughout 1970s 1980s relatively modest earthquakes, 1979 Imperial Valley, California; 1983 Coalinga, California 1984 Morgan Hill, indicated problems associated with improperly detailed this construction type. few placed during period, largely because there examples This began change 1985 Mexico City, earthquake several large buildings lake bed region City collapsed. Additional 1987 Whittier Narrows, Most pertained braced frames. 1994 Northridge, resulted introduction extensive moment-resisting Immediately earthquake, brittle fractures discovered beam column connections Valley (Figures 1, 2). damage was