The Effect of High-Rise Building Cross-Section On The Design Wind Load

• Main Authors: Chung-Tai Liu, 劉中泰
• Other Authors: Chii-Ming Cheng
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/59268497804651857986

碩士 === 淡江大學 === 土木工程學系 === 89 === Title of Thesis： Total pages：156 The Effect of High-Rise Building Cross-Section On The Design Wind Load Name of Institute：Graduate Institute of Civil Engineering , Tamkang University Graduate Date： July, 2001 Degree Conferred：Master of Science Name of Student：Chung-Tai Liu Advisor：Dr. Chii-Ming Cheng 劉 中 泰 鄭 啟 明 博士 Abstract： In a modern city where land is expansive, high-rise building plays a important role in city development. For high-rise buildings, wind force is an important lateral design load besides earthquake force. At present, design wind load is treated as a static force in the official building code. It can’t describe the random nature of the wind force. So, high-rise buildings’ wind tunnel experiment is a better procedure to estimate the wind load. For pleasing to the eye, building tends to have various shapes. Therefore, it becomes important to apprehend the effect of building cross-section on the design wind load. This paper is to measure the wind forces acting on the four different series of building cross-section in both urban flow and city flow field. The four series of cross-section are (1)pure polygon cross-section, (2)rectangular with different width/depth ratio, (3)different form of L cross-section, (4) irregular cross-section. The volume, cross-section area and height of all models are identical to a square prism with aspect ratio of 7. Based on the selection procedure developed by the wind tunnel laboratory of Colorado State University, several critical load cases were selected for the design purpose. After analyzing, the design wind load at each floor of the target building can be calculated. The experimental results indicate that, if peak load is greater that can cause greater design wind load. Most models have greater design wind load in city flow field. Pure polygon cross-section model has less wind force. And circular shape can decrease design wind load effectively. Comparing the experiment of the rectangular shape models, increasing the width/depth ration can decrease lateral design wind load but raise torsional design wind load. In different form of L cross-section series, these models have unsymmetrical cross-section. Hence, they have greater torsional design wind load than the symmetrical cross-section models. Irregular cross-section also has high design wind load. Key word：high-rise building, wind tunnel experiment, force balance, cross-section, design wind load