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A series of large-scale shaking table tests is conducted for a high-rise building structure subjected to long-period ground motions. A test method is developed to preserve the original dimensions of structural members of a prototype building that has 21 stories with a total height of 80 m. The test specimen consists of a four-story, two-span by one-bay steel moment frame and three substitute layers placed on top of the moment frame. The substitute layers, which consist of concrete slabs and rubber bearings, are arranged to represent the upper stories of the prototype. From preliminary vibration tests, equivalence between the test specimen and the prototype is verified in terms of the lower mode natural periods and corresponding mode shapes. The test specimen when subjected to long-period ground motions exhibits cumulative ductilities more than four times those expected in Japanese seismic design, while the maximum story drifts remain nearly the same as those considered in the design. A number of cyclic inelastic deformations caused fractures at the bottom flanges of beam ends. According to these observations, the combination of large cumulative ductility demand, the weld quality of the field weld connections, and the promotion of strain concentrations at the toe of the bottom flange weld access hole by the presence of floor slabs caused the fractures and resultant smaller cumulative ductility relative to that observed in the bare beam tests. DOI: 10.1061/(ASCE)ST.1943-541X.0000161 CE Database subject headings: Buildings, high-rise; Ground motion; Shaking table tests; Seismic effects; Beams; Columns; Connections. Author keywords: High-rise building; Long-period ground motion; Shaking table test; Seismic performance; Beam-to-column connections.

A new type of earthquake-resisting element, consisting of a steel plate shear wall with vertical slits, is introduced. In this system, the steel plate segments between the slits behave as a series of flexural links, which provide a fairly ductile response without the need for heavy stiffening of the wall. Test results are presented for 42 wall plate specimens of roughly one-third of full scale, which were subjected to static monotonic and cyclic lateral loading. These tests provide data on general behavior of the walls, which provides the basis for models to calculate the wall strength and stiffness and design the out-of-plane stiffening. When properly detailed and fabricated to avoid premature failure due to tearing or out-of-plane buckling, the wall panels respond in a ductile manner, with a concentration of inelastic action at the top and bottom of the flexural links. The test data indicate that limiting the width-to-thickness ratio to less than 20 in the flexural links will ensure that the walls can sustain roughly 3% drift without substantial hysteretic degradation. DOI: 10.1061/(ASCE)0733-9445(2003)129:5(586) CE Database subject headings: Buildings; Buckling; Cyclic tests; Earthquake engineering; Steel; Shear walls; Hysteresis.

A series of large-scale shaking table tests is conducted for a high-rise building structure subjected to long-period ground motions. A test method is developed to preserve the original dimensions of structural members of a prototype building that has 21 stories with a total height of 80 m. The test specimen consists of a four-story, two-span by one-bay steel moment frame and three substitute layers placed on top of the moment frame. The substitute layers, which consist of concrete slabs and rubber bearings, are arranged to represent the upper stories of the prototype. From preliminary vibration tests, equivalence between the test specimen and the prototype is verified in terms of the lower mode natural periods and corresponding mode shapes. The test specimen when subjected to long-period ground motions exhibits cumulative ductilities more than four times those expected in Japanese seismic design, while the maximum story drifts remain nearly the same as those considered in the design. A number of cyclic inelastic deformations caused fractures at the bottom flanges of beam ends. According to these observations, the combination of large cumulative ductility demand, the weld quality of the field weld connections, and the promotion of strain concentrations at the toe of the bottom flange weld access hole by the presence of floor slabs caused the fractures and resultant smaller cumulative ductility relative to that observed in the bare beam tests. [ABSTRACT FROM AUTHOR]