Slotted Bolted Connections (SBCs) are modified bolted connections designed to dissipate energy through friction during rectilinear tension and compression loading cycles. Experimental results on two types of SBCs are reported. In one type, friction occurs between clean mill scale steel surfaces; in the other, friction is between clean mill scale steel and brass surfaces. The behavior of connections with brass on steel frictional surfaces is found to be more uniform and simpler to model analytically than that with steel on steel surfaces. These connections maintain essentially constant slip force, and unlike those with steel on steel surfaces, require minimal overstrength of the system in design. The frictional mechanisms giving rise to the observed behavior are explained. As an example of application a one story diagonally braced frame was designed and its behavior determined for four different earthquakes. Experimental results are presented for the fabricated SBC for this frame subjected consecutively to the four displacement histories derived from these earthquakes. The agreement between the analytical and experimental results is found to be excellent. Because of the intrinsic simplicity of the SBCs and their very low cost, their use in seismic design and retrofit applications appears to be very promising.

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Summary The purpose of this article is to present a new method of analysis for the structural design of pin‐supported rocking wall‐moment frames with supplementary devices and post‐tensioned stabilizers. The function of the wall is to prevent soft story failure, impose uniform drift and provide support for the supplementary equipment. The proposed methodology lends itself well to several seismic design strategies, ranging from severe damage avoidance, to collapse prevention, to structural self‐alignment and repairability. Repairability means avoiding major damage to columns and foundations. The success of the resulting solutions is due to the single degree of freedom behavior of the combined system and the fact that its overall performance is not significantly affected by minor changes in the stiffness of the wall. The sensitivity of the response to wall rigidity is addressed by comparing the maximum elastic slope of the wall with a fraction of the specified uniform drift. The limitations of rocking wall‐moment frames, as viable lateral resisting systems, have been addressed. Several worked examples have been presented to provide insight and technical information that may not be readily available from electronic output. The proposed solutions are exact within the bounds of the theoretical assumptions and are ideally suited for manual as well as spreadsheet computations. Copyright © 2015 John Wiley & Sons, Ltd.

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The code stipulated seismic force requirements for buildings from the historical point of view are described first. This is followed by examples of the emerging criteria of inelastic seismic spectra for displacement ductility, and number of yield reversals as a function of building period and strength. Novel spatial representations of seismic input energy and hysteresis energy, interpreted as damage energy, are given next. The available structural resistance countering the imposed seismic demand is illustrated by the ductile behavior of steel moment resisting frames (MRFs) and eccentrically braced frames (EBFs). A discussion of a practical and versatile frictional energy dissipating connection is given at the end.