9317876 9412905 Reinhold Tieleman The project will develop improved methods for the simulation and analysis of extreme wind loads on low-rise structures and will examine the safety factors for these structures when subject to upwind roughness fields of random height and fetch. The work includes the following tasks: develop turbulence simulation and turbulence augmentation techniques with assessment of the effects on peak suctions; simultaneous measurements of incident velocity fluctuations and surface pressures; analysis of data using eigenvector techniques and conditional sampling; develop criteria for modeling wind loads including extreme suctions; measure incident velocities; velocities of vortices and surface pressures for various building shapes and flows; conduct similar tests including abrupt changes in roughness; and test a group of buildings including random variations of surrounding roughness and buildings. The results from this work will help in the development of methods for mitigating the effect of intense surface pressures fluctuations due to flow separation and vortex generation in low-raise buildings along roof-wall intersections. ***