The lack of clear guidance regarding the value of elastic flexural rigidity (EI) that should be used in the analysis of steel-concrete composite columns is a significant unresolved issue that hinders the design of frame systems that include these members. The common approach of utilizing the rigidity of either the steel or the concrete only tends to be overly conservative. Other approaches that...

The floor beams of steel buildings, cold-formed steel floor joists in particular, often require large web openings, which may affect their shear capacities. A cost effective way to mitigate the detrimental effects of such openings is to weld/fasten reinforcements. A difficulty associated with an experimental investigation to establish suitable reinforcement schemes for openings in shear zone is...

One of the typically damaged steel beam-column connection during the Northridge earthquake of 1994 was bolted-web, welded-flange (BWWF), now known as “pre-Northridge” connection. Proposed post-Northridge connections are more ductile and capable of dissipating more energy, thus improving the behavior of steel moment resisting frames (SMRF). The post-Northridge connections with added ductility wi...

Buckling-Restrained Braced Frame system(BRBFs) are a new type of steel seismic-load-resisting system that has found use in several countries because of its efficiency and its promise of seismic performance far superior to that of conventional braced frames. The system is addressed in the 2005 edition of the AISC Seismic Provisions for Structural Steel Buildings, also a set of design provisions ...

In this paper, moment-curvature behavior and ductility of prestressed concrete members based on nonlinear analysis is investigated. Influence of various design parameters on ductility of flexural members is determined according to appropriate materials models for stress-strain curves of concrete, prestressing steel and conventional reinforcements. Parameters studied include reinforcing index (ω...

Computational cost of metaheuristic based optimum design algorithms grows excessively with structure size. This results in computational inefficiency of modern metaheuristic algorithms in tackling optimum design problems of large scale structural systems. This paper attempts to provide a computationally efficient optimization tool for optimum design of large scale steel frame structures to AISC...