FINITE ELEMENT ANALYSIS ON A LARGE-SPAN TRANSMISSION TOWER WITH BUILT-UP COLUMNS
Fang Li 1*, Hong-Zhou Deng 1
1 Department of Structural Engineering, Tongji University, Shanghai, China
In this paper, mechanical performance of a new type of large-span transmission tower (455 meters high) is analyzed by adopting finite element (FE) software ANSYS. The significant difference between this new tower with regular ones lies in the tower's legs. In the new tower, each leg is a built-up column, which is constituted with four steel tubes. At the position of each joint, connecting beams (CBs) are arranged to join the four tubes in the built-up column together. Thus, force distribution and transmission in this tower are more complex than regular towers with the leg comprising only one tube. Axial force distribution and deviation in the built-up columns were studied under 45°, 60° and 90° wind. Then, under the control load case, the layout and stiffness variation of the CBs in the joint zone was analyzed. Results indicated that with the increase of the CBs' stiffness, the percentage of axial force unevenness and total stress unevenness in the built-up column decreased. To meet the requests of both economy and mechanical performance, section dimensions of the CBs with triple linear stiffness to QSTC’s were recommended.
transmission tower; built-up column; mechanical performance; finite element analysis; steel tubes; connecting beams