台风作用下门式刚架结构减压抗倾的数值模拟分析

Numerical Simulation of Decompression and Anti-Overturning for Portal Frame Structure in the Case of Typhoon

经初步核算某船厂拟建门式刚架风雨棚结构,不能满足50 a一遇台风工况下的结构抗倾覆稳定性要求。故本文根据实际工程需求,采取在两侧各布设两个通风窗户以达到一定的减压抗倾效果,并通过数值模拟手段验证其减压、抗倾覆性能。对比分析发现20 a和50 a一遇台风工况下压力与倾覆力矩的数值计算值与理论计算值符合良好,并且进一步验证了增设窗户可有效减小迎风面的压力和背风面的吸力,整体减压抗倾效果显著。门式刚架结构满足50 a一遇台风工况下抗倾设计要求。此外,还得到的关于门式刚架表面风压分布规律的相关结论,为该类建筑物结构设计与工程安全性改进提供了一定依据。

Based on preliminary calculation,it has been confirmed that a portal frame shelter structure of some shipyard intending to build can not satisfy the anti-overturning stability requirement in the case of 50-year return period （T-50） typhoon condition.Therefore,some measures （i.e.adding two windows on each side in this paper） have been taken to enhance the decompression and anti-overturning ability,and numerical simulations have been adopted to verify their effectiveness.By comparing the theoretical and numerical results of pressure and overturning moment （OM） in the case of 20-and 50-year return period typhoon conditions,it has been found that the results from numerical simulation agree well with those from theoretical calculation.Subsequently,it has been verified that the pressure of windward side and suction of leeside have beendecreased due to the existence of windows,and the decompression and anti-overturning effect is obviously.As a result,the overturning design in the case of 50-year return period typhoon conditions is satisfied.In addition,the observed conclusions about the rule of surface wind pressure distribution provide some references for the structural design and engineering safety improvement for similar ocean structures.