沿海高耸塔器抗台风安全性能评估

On the safety performance reliability assessment of the typhoon-resistant tall-elevated tower

针对沿海台风频发地区高耸塔器结构安全评估问题,采用有限元方法,对某塔器在不同液位状态与不同台风等级组合工况下的结构强度进行了定量评估,结果表明:该塔器轴向拉应力在12级台风作用下即不满足设计要求。进一步基于Pushover方法对该塔器进行非线性静力推覆分析,得到该塔器的整体极限抗台风能力及弱点位置。在此基础上,提出斜拉筋加固方案,加固后的塔器能够满足15级台风的强度设计要求,且具有较大安全裕量;斜拉筋加固方案能够显著改善塔器结构受力状态,有效提高其抗台风能力。

In order to assess the anti-typhoon performance of the marine cost tall-elevated tower（ TET） quantitatively,this paper has proposed an evaluation approach based on the finite element analysis（ FEA）. For the said purpose,we have established a numerical model of a HRT accurately set up via the FEA software ANSYS. To promote the success of the simulated research,we have done 12 different analysis cases by combining the 3 operational liquid levels and four typhoon grades,so as to make an analysis of the axial compressive stress and the axial tensile stress of the dangerous sections of the tower skirt and the 4 cylinders.The analysis results have shown that cylinder 4 can satisfy the design requirement under the 15 th-grade typhoon,but cylinder 1 and cylinder 2 plus the tower skirt fail to satisfy the demand even under the 14 thlevel typhoon. Needless to say,cylinder 1 is the weakest component of the tower,and therefore,it cannot withstand the 12 th-grade typhoon. And,then,when the Pushover method was applied to test the overall safety performance of the tower in consideration of the geometric and material nonlinearity,we have found that the maximum resistance of the tower should be less than the total wind loading of the 17 thgrade typhoon. Thismay imply that it would be getting to collapse under the 17 thor higher levels of typhoon. To enhance the resistance power of the anti-typhoon tower,we have worked out a reinforcement scheme by using 3 stayed-cables, with each one arranged along the circumferential tower with 120° intervals, whereas the angle between the stayed-cable and the tower has been chosen as 60°.In proceeding with the test,one end of the stayed-cable is supposed to be fixed on the middle height of the tower with the other anchored on the ground. It turns out that the strengthened tower can satisfy the strength demand in case it is subjected to the 15 th level typhoon with enough strength allowance. Of course,the reinforcement scheme should be able to improve the stress distribution and reduce both of the axial compressive stress and the axial tensile stress of the tower obviously. And,consequently,it is natural that the tower to be designed can be made to heighten the typhoon-resistant capability dramatically to enhance its resistance power much greater,but what we have done is just to be aimed for providing a reference approach to the improvement of the evaluation and the TET design under the hit of the strong typhoons.