Wind Load Factors for Tall Building Design and the ASCE 7 Standard

Published

February 19, 2017

Author(s)

Rene D. Gabbai, Emil Simiu

Abstract

Wind load factors incorporated in the ASCE 7 Standard are based on rough approximations of wind effects and the uncertainties inherent in them. These factors are routinely applied to tall building design, even though the original calculations on which they are based do not account for two important facts characterizing tall building response to wind. First, wind effects on flexible structures are proportional to the wind speeds raised to powers larger than two, instead of the power two, as is the case for rigid buildings. Second, dynamic response parameters, that is, the natural frequencies of vibration and the damping ratios affecting the response, exhibit significant uncertainties. It is shown that, for these reasons, the use of ASCE 7 wind load factors for the de-sign of tall flexible buildings results in safety levels that can be significantly lower than safety levels typical of common, rigid structures. In this paper we use newly developed capabilities that account for wind directionality effects and allow the automated design of members wherein wind effects and wind load factors are member-specific.

Proceedings Title

International Conference on Wind Engineering | 12th | 2007 | ICWD

Conference Dates

July 1-6, 2007

Conference Location

Cairns, 1, AS

Conference Title

International Conference on Wind Engineering

Pub Type

Conferences

Keywords

building technology, structural engineering, tall buildings, wind engineering, wind forces, wind load factors

Citation

Gabbai, R. and Simiu, E. (2017), Wind Load Factors for Tall Building Design and the ASCE 7 Standard, International Conference on Wind Engineering | 12th | 2007 | ICWD, Cairns, 1, AS (Accessed December 14, 2024)