Vibrações Induzidas pelo Vento em Edifícios Altos: Critérios de Conforto

Maria Teresa Queiroga Ferreira

Key information

Authors:

Maria Teresa Queiroga Ferreira (Maria Teresa Queiroga Ferreira Montalvão)

Supervisors:

João Carlos De Oliveira Fernandes de Almeida (João Carlos De Oliveira Fernandes de Almeida)

Published in

November 24, 2009

Abstract

Modern tall buildings are expected to meet certain acceleration limits to ensure occupant comfort due to building motions. The subjective nature of human perception and tolerance of wind-induced tall building vibration, and, the uncertainty associated with the parameters in the occupant comfort checking procedure lead to the currently no single internationally accepted occupant comfort serviceability criteria. In this document, building vibration acceptability and occupant comfort criteria that have been commonly adopted for the assessment of occupant comfort in wind-excited tall buildings are outlined. In order to reduce wind loads and their effect on tall building motions, various shaping strategies and structural configuration are discussed with recent application, aimed particularly at suppression of vortex shedding since it is frequently the cause of crosswind excitation. The use of supplementary damping systems is another approach that takes the energy out of building motions and reduces loads. Therefore, this document also presents a few auxiliary damping devices and describes different applications of these damping systems on several buildings. For the assessment of the wind-induced acceleration on the top of tall buildings a few methods are discussed, such as, computational fluid dynamics and wind tunnel experiences, that include the high frequency force balance tests, high frequency pressure integration tests, aeroelastic modeling and high Reynolds number tests. In light of the significance of the assessment acceleration on the top of a tall building, two international codes are discussed, through an analytical and numerical comparison. The latter was made applying two real case studies on both codes.