THESIS
2014
xviii, 147 pages : illustrations ; 30 cm
Abstract
Accurate estimation of the dynamic structural response to wind excitations is crucial to the
wind-resistant design of tall buildings, which is commonly done by the high frequency base
balance (HFBB) testing technique. The recent trend of constructing tall buildings in city centers
with high proximity of surrounding buildings increases the occurrence and significance of wind
interference effects. Such interference effects significantly alter the characteristics of the wind
loads on the tall buildings, and can significantly affect the performance of the HFBB methods.
The principal objectives of this research are to identify the interference effects on a benchmark
rectangular wind-sensitive tall building in a region where there are short and tall surrounding
buildings, investigate...[
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Accurate estimation of the dynamic structural response to wind excitations is crucial to the
wind-resistant design of tall buildings, which is commonly done by the high frequency base
balance (HFBB) testing technique. The recent trend of constructing tall buildings in city centers
with high proximity of surrounding buildings increases the occurrence and significance of wind
interference effects. Such interference effects significantly alter the characteristics of the wind
loads on the tall buildings, and can significantly affect the performance of the HFBB methods.
The principal objectives of this research are to identify the interference effects on a benchmark
rectangular wind-sensitive tall building in a region where there are short and tall surrounding
buildings, investigate the change of the wind force characteristics due to the interference effects,
and evaluate the corresponding effect on the performance of the HFBB methods.
The wind tunnel test data of three interfering models are analyzed and five interference effect
mechanisms are identified. The results show that the location and strength of the interference
effect mechanisms depend on the height of the interfering buildings. Based on the study of the
interference effect mechanisms, the interference effects on the wind force characteristics on the
benchmark building are investigated.
The interference effects on the HFBB methods due to the changed vertical distribution of the
fluctuation component of the local wind forces are investigated. In-house non-coupled mode
shapes are created based on the original mode shapes of the benchmark building. The
performance of the HFBB methods, under a power law distribution assumption and a uniform
distribution assumption of the local force spectrum distribution, are compared in the in-house
mode shape. The results show that the uniform distribution assumption of the local force
spectrum distribution is unreliable and the power law assumption is necessary under conditions
with interfering effects. The interference effects on the HFBB methods due to the changed
cross-correlation conditions of the local wind forces is also investigated. The performance of
the HFBB methods, under no and full correlation assumptions between the local forces, are
compared in the in-house mode shape. The results show that the performance of the no
correlation assumption is better than the full correlation assumption in torsional wind excitation.
Coupled mode shapes are created and tested. For coupled mode shapes, each base moment
should use the corresponding HFBB method, based on the cross-correlation condition of the
wind excitation.
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