NEW PERCEPTIONS ON THE STRUCTURE BEHAVIOR OF HYPERBOLOIDAL COOLING TOWERS

The strucuture behavior of a hyperboloidal cooling tower was illustrated based on the analysis of dynamic properties and equivalent static wind load effects according to some basic properties drawn from horizontal ring structures and meridian cantilever beams.It was shown that as a thin-wall and high-rise structure with circular cross section,the strucuture behavior of a cooling tower reflects both that of horizontal rings and meridian cantilever beams.Its mode shapes can be deemed as the coupling of mode shapes of horizontal rings (stripe) supported elastically at top and bottom edges and meridian cantilever beams (stripe) supported elastically in right and left sides,and the natural frequencies are much influenced by the latitude stiffness.The displacement and internal forces have similar latitude distribution with the distribution of external wind pressure C_P(θ).The maximum of displacement and internal forces are all primarily influenced by the windward and sideward wind pressure,and consequently dominated greatly by the non-uniformity of C_P(θ).The latitude distribution of meridian axis force provides the resisting overturning moment implicitly and it aggregates downward along the height as the overturning moment,whics is the reflection of structural behaviors of meridian cantilever beams.In addition,the aggregation is influenced by the meridian curve.