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This report looks at the benefits of using CFT braces and the relevant issues associated with their design, analysis, fabrication, and constructability. It is concluded that the use of CFT braces is an attractive option in terms of steel material cost and reduction of erection labor/time.

Prominently located at a major intersection along Beijing's second ring road, northeast of the Forbidden City, the 110m tall New Beijing Poly Plaza project includes 24 stories of office space, an eight-story hanging museum `lantern' and a 90m tall atrium enclosed by what is believed to be the world's largest cable-net supported glass wall — a challenge amplified by the region's high seismicity. The cable-net wall is 90m high by 60m wide — dimensions that make a simple cable-net supported wall require uneconomical cable sizes and levels of pre-stress. The design is achieved by folding the cable-net around diagonal `V'-shaped, parallel-strand bridge cables, thus subdividing the wall into three planar facets and reducing the effective cable spans. The parallel-strand cables also support the `lantern' as it hangs in the atrium space without any columns extending to grade. Gravity loads from the `lantern' are used to induce high levels of tension or pre-stress in the parallel-strand cables. As the parallel-strand cables diagonally connect diaphragms that are 11 stories apart, lateral drift in the base building causes brace forces in the diagonal cables, increasing the design forces beyond reasonable levels. An innovative `rocker' mechanism is used to isolate the cable hanger system from forces induced by seismic drift. The `rocker' mechanism is architecturally `celebrated' — an exposed articulated joint mechanism made of rigid pin-connected castings which perform as a pulley equivalent. The mechanism allows the `V'-shaped parallel strand cables to behave as a continuous cable running around a pulley, offsetting induced tensile and compressive brace forces in the cables as the building drifts.

In current seismic design practice, AASHTO, AREMA and IBC are the most popular specifications for highway bridges, railway bridges and building structures, respectively. Theoretical speaking, when earthquakes occurred, the structures would be damaged with no exception regardless of their functionalities. But the seismic design approaches and requirements in these three specifications demonstrate significant differences in many aspects. It is necessary to make a systematic comparison of these three specifications in terms of seismic design in order to carry out reasonable seismic analysis on some multi-function structures which are including building structure and bridges for vehicles or trains, or both. A good example of this type of structures is multi-model transportation center which is normally appearing in metropolitan area. In the seismic analysis of this type of structure, some additional coordination work among these specifications is critical in order to achieve correct results. Theoretical parametric investigations have been made to compare these three specifications in terms of seismic design. Some recommendations are provided for seismic analysis of this type of multi-function structures.

In late 1970s internationally renowned artists Christo and Jeanne-Claude deigned a Mastaba for the United Arab Emirates (UAE). A mastaba (Arabic word for a bench) resembles a truncated pyramid with two vertical walls and two inclined walls. The proposed structure measures 150 meters in height and is 300 meters by 225 meters at the base. It is large enough to house the largest Egyptian pyramid in Giza inside it. The artists designed the proposed monument as an enclosure only with no utilization of the space inside at any time. The Mastaba of UAE is to be located in a seismic zone covered on all four sides as well as the roof with about 400,000 horizontally placed 55-gallon steel oil barrels of varying brilliant colors acting as facade. Given that the entire Mastaba is a work of art, the patterns of barrel colors are established by the artists. The proposed monument is to stand alone with no facilities within the vicinity of the structure.

In November 2008, ACI published a new document, Code Requirements for Reinforced Concrete Chimneys (ACI 307-08). (Ref. 1) This new document replaces the existing chimney design standard, Design and Construction of Reinforced Concrete Chimneys (ACI 307-98). (Ref. 2) The new chimney code incorporates a number of major technical revisions. One of the more significant changes is pertinent to seismic design provisions. The new seismic design provisions include several key changes from the previous edition: namely, selecting the design base earthquake as 2/3 of MCE (Maximum Considered Earthquake), including effects of soil amplification in design response spectra, use of a response modification factor (R) of 1.50, considering the P-delta effects for chimneys of seismic design category D, E and F, and adding a seismic clearance criterion between the concrete chimney shell and chimney liner(s).

This study aims to qualitatively describe the seismic behavior of container cranes. Due to the nature of container crane construction, the portal frame in a crane is highlighted as the controlling aspect for seismic performance. Notably, the effects of the portal frame structural response and the uplift/rocking response are considered in depth. A detailed finite element model is used to consider a case-study container crane to verify and expand our understanding of the seismic behavior. It is found that the coupling between portal frame response and rocking is critical, especially when evaluating performance nearing ultimate. There is a narrow margin between first yielding and potential structural collapse. Several general strategies are proposed to design safer, more resilient cranes in the future.

This paper will discuss the effects of large deformations and stiffeners on the behavior and design of gusset plates. It will also present a procedure to predict the inherent moment resistance of beam-to-column vertical bracing connections.

This paper deals with the seismic design and ductility evaluation of partially concrete-filled steel box columns. The effects of residual stresses on seismic capacity prediction of partially concrete-filled steel box columns are investigated. Recently, Mamaghani and his co-workers have developed a seismic design method for ultimate strength and ductility evaluation of hollow and concrete-filled thin-walled steel tubular beam-columns [1]. The method involves an elastoplastic pushover analysis and definition of failure criterion taking into account local buckling ignoring residual stresses. In this study the method is modified for the effect of residual stresses. The application of the method is demonstrated by comparing the computed strength and ductility of some cantilever beam-columns with test results. The interaction between the effects of residual stresses and some important parameters, such as width-to-thickness ratio, column slenderness ratio and height of infill concrete, on the ultimate strength and ductility of thin-walled steel tubular beam-columns, are presented and discussed.