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In this research an attempt has been made in order to determine the efficiency of different types of structural systems at different heights up to 30 stories (300 feet). The investigation has been carried out on three types of lateral load resisting systems i.e. moment resisting frame, building frame system and outrigger braced frame system for seismic zone 2B as per UBC 1997 considering dead, live, seismic, wind load and their combinations. It was found that up to a 5 story building (50 feet) moment resisting frame was found more cost efficient as moment resisting frame was found stiff enough to resist lateral load and addition of shear wall was not required for further increase in stiffness. From 6 story building up to 20 story building (200 feet) building frame system was found more cost efficient and from 21 story building and beyond outrigger braced frame system was found more cost efficient. Accordingly, from one to five story buildings were categorized as low rise, from six to nineteen story buildings as medium rise and from twenty stories onwards as high rise buildings.

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This paper presents the results of variation in column spacing of a tube in its outer periphery concerning structural drift and cost optimization. For high rise structures, tubular framing and outrigger braced frames are considered as the most appropriate solution economically. In recent past not must study has been focused on the tubular frame in its columns spacing and span length. In this research, a simple square plan structure has been considered with different heights of 30, 40, and 50 story buildings. Six different framing systems of the tubular structure have been developed with different column spacing in each and employed to each high-rise structure. Concrete strength and steel yield strength has been taken as a fixed value for every model. Several models were developed with these combinations and the drift and structural safety have been optimized by reducing the cross-section sizes in each system. Seismic analysis has been carried out to evaluate the effects of varying column spacing in each tube. The comparison of all the employed systems was carried out and cost analysis has been made. Observations have been taken from drift, base shear, and cost analysis of each framing system of the tube, and certain results were concluded for structures with different height.