Dependence of surface pressures on a cubic building in tornado like flow on building location and ground roughness

Abstract Violent wind vortices and their influence on structures have been an area of research during the past few decades. Effects of these vortices on building structures depend on vortex size relative to building size, relative distance between vortex center and building location, terrain condition and swirl ratio. The present investigation takes into account factors such as building model location with respect to vortex center and terrain condition that influence the surface pressures on a building model cube exposed to a swirl flow by performing a systematic set of laboratory experiments using a Ward-type tornado-like-flow simulator developed at Tokyo Polytechnic University, Japan. The developed vortex was stationary and the effect of translation was not taken into account. The scalar component of velocity was determined at different heights and radii across the simulator floor. Mean and peak pressures acting on the building model cube considering the effect of the above factors is discussed. Salient features of peak pressure coefficients on a building surface occurring under a tornado-like flow regime are also discussed.

[1]  C. C. Chang,et al.  Measurement of the Velocity Field in a Simulated Tornado-Like Vortex Using a Three-Dimensional Velocity Probe , 1972 .

[2]  Influence of incident flow conditions on generation of tornado-like flow , 2009 .

[3]  T. Maruyama,et al.  Simulation of flying debris using a numerically generated tornado-like vortex , 2011 .

[4]  Jean Dessens Influence of Ground Roughness on Tornadoes: A Laboratory Simulation , 1972 .

[5]  Hiroshi Niino,et al.  A Statistical Study of Tornadoes and Waterspouts in Japan from 1961 to 1993 , 1997 .

[6]  Chris Letchford,et al.  Physical simulation of a single-celled tornado-like vortex, Part A: Flow field characterization , 2008 .

[7]  Hui Hu,et al.  An experimental study of a high-rise building model in tornado-like winds , 2011 .

[8]  R. Panneer Selvam,et al.  Computer modeling of tornado forces on buildings , 2003 .

[9]  Horia Hangan,et al.  Experimental investigation of tornado-like vortex dynamics with swirl ratio: The mean and turbulent flow fields , 2010 .

[10]  W. S. Lewellen,et al.  Large-Eddy Simulation of a Tornado’s Interaction with the Surface , 1997 .

[11]  Chris Letchford,et al.  Physical Simulation of a Single-Celled Tornado-Like Vortex, Part B: Wind Loading on a Cubical Model , 2008 .

[12]  Fred W. Leslie,et al.  Surface Roughness Effects on Suction Vortex Formation: A Laboratory Simulation , 1977 .

[13]  Horia Hangan,et al.  Swirl ratio effects on tornado vortices in relation to the Fujita scale , 2008 .

[14]  Neil B. Ward,et al.  The Exploration of Certain Features of Tornado Dynamics Using a Laboratory Model , 1972 .

[15]  John T. Snow,et al.  Characteristics of Tornado-Like Vortices as a Function of Swirl Ratio: A Laboratory Investigation , 1979 .

[16]  G.C.K. Yeh Differential pressures on building walls during tornadoes , 1977 .

[17]  Therese P. McAllister,et al.  Design Guidelines for Community Shelters for Extreme Wind Events , 2002 .

[18]  Yukio Tamura,et al.  Fluctuating Pressures on Cube Faces and Simulator Floor Intornado-Like Flow , 2009 .

[19]  Christopher R. Church,et al.  Measurements of Core Radii and Peak Velocities in Modeled Atmospheric Vortices , 1979 .

[20]  Partha P. Sarkar,et al.  Tornado-induced wind loads on a low-rise building , 2010 .

[21]  James R. McDonald,et al.  Windspeeds Analyses of April 3-4, 1974 Tornadoes , 1976 .

[22]  M. C. Jischke,et al.  Laboratory simulation of tornadic wind loads on a rectangular model structure , 1983 .

[23]  P. K Dutta,et al.  Dynamic response of structures subjected to tornado loads by FEM , 2002 .