THE ROLE OF WIND-TUNNEL TESTING IN THE DESIGN OF BUILDING STRUCTURES

The estimation of wind effects on and around building structures is an inexact science, Wind forces are dynamic and fluctuate continuously i n both magnitude and position, In most modern wind codes, wind loads a re represented as idealized uniform static loads for generalized build ing forms, For most building structures these codified values are adeq uate, However, these codes have their limitations and do not apply in the following cases, to quote CP 3, 'to buildings that are of unusual geometric shape, or have unusual site locations warranting special con sideration' or 'to buildings whose structural properties,,,make them s usceptible to dynamic excitation', In these cases the code specificall y recommends the use of experimental methods which includes properly c onducted wind tunnel tests, The use of experimental methods is also re commended 'when wind loading data are required in more detail than is given in this Code, or when the form of the building can be changed in response to the test results in order to give an optimal design', Thi s paper describes the role of wind tunnel testing in the design of bui lding structures and discusses situations where these tests are likely to be cost-effective and improve the reliability of the wind loads an d wind environment, Reference is made, wherever possible, to case stud ies.