Experimental study on the interference intensity produced by the presence of neighboring buildings in the wind action in a tall building

Abstract

Experimental study on the interference intensity produced by the presence of neighboring buildings in the wind action in a tall building Estudo experimental sobre a intensidade da interferência produzida, pela presença de edifícios vizinhos, na ação do vento em um edifício alto Abstract ResumoThe average strain on a building due to the action of the wind, can be significantly altered when considering the presence of one or more neighboring buildings. Such changes can be considered through the use of coefficients that take into account the distance that the neighboring building is from the building being studied. The present work was developed in order to verify the values currently adopted by the Brazilian standard that regulates the wind action in buildings. With the use of a wind tunnel, several tests were carried out in a standardized building considering the presence of other buildings with similar dimensions close to it. The distances between the buildings, the quantity and the layout of the neighboring buildings were taken into consideration. It was possible to conclude that, in general, the presence of the neighboring buildings produced an increase on the strain. Interference, in many situations, increased strain above the rates suggested by the current Brazilian wind action standard. Keywords: wind action, neighborhood effects, aerodynamics of buildings.Os esforços médios atuantes em uma edificação devidos à ação do vento, podem ser significativamente alterados quando se considera a presença de um ou mais edifícios vizinhos. Tais alterações podem ser consideradas através da utilização de coeficientes que levem em conta a distância que o edifício vizinho está da edificação em estudo. O presente trabalho foi desenvolvido no intuito de verificar os valores atualmente adotados pela norma brasileira que regula a ação do vento em edificações. Com a utilização de um túnel de vento, foram feitos vários ensaios em um edifício padronizado considerando a presença de outros edifícios com dimensões idênticas próximos a ele. Considerou-se o afastamento entre os edifícios, além da quantidade e da disposição das edificações vizinhas. Pôde-se concluir que, de maneira geral, a presença das edificações vizinhas produziu a majoração dos esforços. As interferências, em muitas situações, elevaram os esforços acima dos índices sugeridos pela atual norma brasileira de ação do vento.Palavras-chave: ação do vento, efeitos de vizinhança, aerodinâmica de construções.

Numerical-experimental study of neighboring wind effects on tall buildings related to serviceability via reliability

“…Figure 2 depicts the standardized CAARC full-scale building with the arrangement of the 280 pressure plug indicators, in which the base center coincides with the building's vertical axis. More details can be seen in [19] and [20]. The building has a flat horizontal roof without parapet, with smooth facades and no geometric particularities, and dimensions of 100 ft x 150 ft x 600 ft (base dimensions and height), equivalent to 30.48 m x 45.72 m x 182.88 m [27].…”

“…With the raise of neighborhoods, determined by the sort of arrangement, wind protection effects or even more motions can be generated in a pre-existing building due to reconfiguration of the wind flow (Blessmann [10], [11], Blessmann and Riera [12], [13]). Studies have shown, with use of reduced scale models in wind tunnel, such as Yu et al [14], Hui et al [15], Fontoura [16], Kim et al [17], [18], Vieira et al [19], [20], Lavôr [21], among others, that the presence of buildings in the neighboring regions results in modifications of wind forces, pressures and aerodynamic coefficients.…”

Experimental study in wind tunnel of interference effects on the reduced model of the CAARC building

“…Considering that the peak pressures measured in the tests do not act simultaneously on the entire structure of the model, the mean pressures can be integrated to provide mean values of shear forces and bending moments acting on the building. The force coefficients in the direction of the x and y axes are given by the ratio between the vector sum of the forces acting in the area of influence of each pressure tap and the product of the dynamic pressure by the total area of incidence of the wind, in relation to the x and y axes (Loredo-Souza et al, 2006;Vieira et al, 2018):…”