Application of Equivalent Static Wind Loads on Bridge Design

• Main Authors: Ping Wang, 王彬
• Other Authors: Yuh-Yi Lin
• Format: Others
• Language: zh-TW
• Published: 2013
• Online Access: http://ndltd.ncl.edu.tw/handle/22249014234983331526

碩士 === 淡江大學 === 土木工程學系碩士班 === 101 === The number of cable-supported bridges completed or under construction has been increasing in recent years. For this type of bridges, wind loads become significant and should be considered in bridge design. However, incorporating both static and dynamic wind loads for design use is still a tedious and difficult task. In current domestic engineering practice, wind tunnel testing is used for confirmation only. Since wind loads play a more dominant role as bridge spans become longer, these loads should be taken into consideration in the design. In this thesis, an approach to generate equivalent static wind loads at the design wind speed based on the information obtained from wind tunnel testing is proposed. In general, the dynamic responses can be divided into two parts, namely, the background and the resonant responses. Based on the buffeting theory, the resonant part of the buffeting responses contributed by the major structural modes can be derived. The background responses can be expressed in terms of external wind load distribution or inertial load distribution. The former can be derived by using the concept of LRC, while the latter can be derived in a similar way to the resonant responses. Then using the weighting functions and peak factors, the equivalent static wind loads can be generated. To examine the validity of the analytical approach, the results of a simply-supported beam were calculated and compared with those in the literature. The comparison indicates that the results are in good agreements. For demonstrating the applicability of this approach, an example of a cable-stayed bridge in construction was presented. By using this approach, the equivalent static wind loads can be generated and used for design in a combination with other loads.