Improved Limiting Criteria for Deflection in Multi-Story Buildings Subjected to Aerodynamic Load

In recent times, there have been rapid changes in the Architectural design of multi-story buildings tending towards slenderer structures due purposely to space utilization. These changes are not without some inherent challenges on the serviceability requirements of these buildings; of major concern are deflection, oscillation, and excessive vibration developed by the action of wind on the structural members. This study carried out an evaluation of shear wall and frame network subjected to aerodynamic wind load on a 60m, 20 storeys regular building model for aerodynamic resistance of multi-story building with a view to having further improvement on the serviceability criteria. Wind load assessment was carried out in accordance with recommendations of Euro code using critical wind speed of Maiduguri (47m/s) as primary data. Analysis of the structural system was carried out by using approximate rapid manual method and standard software package. An improved equation was developed for deflection from the result of the analysis which satisfies the limiting criteria of the code. Results obtain from the improved equation when compared with the existing limiting criteria shows more flexural rigidity up to about 95% of the height of the building. This means that the improved equation will provide less deflection than the existing method up to 95% of the building, thereby providing more comfort to the occupants of the buildings.