- 摘 要
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（同濟大學土木工程學院， 上海 200092）
［摘要］單鋼管避雷針的長細比過大，剛度較小，在風荷載作用下容易發(fā)生風致振動和渦激振動，導致避雷針的根部或法蘭連接部位的焊縫或螺栓產(chǎn)生疲勞破壞。為了減少避雷針在風荷載下的振動，采取相關減振措施。采用有限元軟件ABAQUS對結構進行建模分析，比較三種減振方案的不同效果。結果表明，基于特制調(diào)頻質(zhì)量阻尼器（TMD）的減振裝置效果好并易于實施，在合理設計下能夠顯著減小振動；而內(nèi)置預應力拉索方案沒有明顯的減振效果；采用灌漿加強的雙法蘭連接構造雖然未能減小振動，但是局部的加強有助于降低關鍵部位的應力水平，進而提高疲勞性能。此外，對格構式避雷針進行建模分析，與單鋼管避雷針比較發(fā)現(xiàn)，格構式避雷針在風荷載下的力學性能優(yōu)于單鋼管式避雷針。
［關鍵詞］避雷針； 減振； 調(diào)頻質(zhì)量阻尼器（TMD）； 預應力拉索； 雙法蘭
中圖分類號：TU895文獻標識碼：A文章編號：1002-848X(2018)13-0020-06
Study on vibration damping design of single-steel-pole lightning rod
Chen Tao, Yao Cheng, Wang Xian, Yu Qianqian
(College of Civil Engineering, Tongji University, Shanghai 200092, China)
Abstract:Due to the large slenderness and small stiffness of the single-steel-pole lightning rod, wind-induced vibrations and vortex-induced vibrations happen frequently under wind load. Vibrations may cause fatigue damage at the root of the lightning rod or weld seams or bolts at the flange joint. Relevant measures were adopted to reduce the vibrations of lightning rods under wind load. Three different damping measures to reduce the vibration were analyzed by finite element software ABAQUS. The results of the analysis show that the damping device based on special tuned mass damper(TMD) can significantly reduce the vibration and it is easy to implement, and its reasonable design can significantly reduce vibration; built-in prestressed cable scheme cannot significantly reduce the vibration; grouting strengthened double-flange structure cannot reduce the vibrations, but local strengthening reduces stress levels at critical locations and improves the fatigue performance. In addition, the lattice typed lightning rod was modeled and analyzed. Compared with the single-steel-pole lightning rod, it is found that the mechanical properties of the lattice typed lightning rod are better than those of the single-steel-pole lightning rod under the wind load.
Keywords:lightning rod; damping; tuned mass damper(TMD); prestressed cable; double-flange
作者簡介：陳濤，博士，副教授，博士生導師，Email: t.chen@#edu.cn。
