Analysis of 91.5 m high flare stack under dynamic loading

Flare stacks are one of the major of civil engineering structures in the refineries. Several factors primarily the development of high strength materials, new design concepts and methods, introduction of new structural systems, improved construction method and the afford ability of modem efficient computing tools have significantly contributed to the continued development of tall structures in last few decades. Although 'Tall Structure' is a relative term, from structural engineering point of view, a Tall Structure can be defined as one whose structural design is governed primarily by the lateral load resisting systems. Simplified 2D analyses method and tools are generally not sufficient for the realistic prediction of the response of such systems that demand the 3D analysis. Because of the dynamic nature of the lateral loads (earthquake loading and wind loading) and requirement for 3D analysis, sophisticated computational tools and techniques are required. This paper is intended to study the behavior and structural system of 91.5 m (300 ft.) high flare stacks at global to component levels, interpretations of the results and finally the design. (author)