The reinforcement design is the most critical and time-consuming process in structural design of hyperbolic cooling tower (HCT) shell due to the complicate internal force distributions and arbitrary direction of wind load. The internal forces of a representative HCT under different loads, including gravity, wind, thermal actions of winter and summer, horizontal and vertical earthquakes with reasonable load values, were illustrated individually and compared systematically. It was found that all the internal forces follow uniform or simple latitude distribution except the wind effects and, therefore, the structural reinforcement design is an easy process when wind load is excluded. However, the participation of wind load make it unpredictable where the most unfavorable internal force condition locates in latitude direction. It is even inevitable that many wind directions must be involved to combine with other loads in reinforcement design calculation. In this study, a virtual uniform distribution is proposed to replace the actual irregular distribution of wind effects, and then, the design calculation procedure is simplified greatly because the multiple wind direction involvement and calculation on the whole latitude shell are both avoided. Meanwhile, the incensement of reinforcement amount got from the simplified procedure is about only 2% and the distribution is more reasonable.

由于复杂的内力分布和任意方向的风荷载，加固设计是双曲线冷却塔（HCT）壳体结构设计中最关键和最耗时的过程。分别说明并系统比较了具有代表性的HCT在不同载荷下的内力，包括重力，风，冬季和夏季的热作用，具有合理载荷值的水平和垂直地震。发现除风作用外，所有内力均服从均匀或简单的纬度分布，因此，在排除风荷载的情况下，结构加固设计是一个简单的过程。然而，风荷载的参与使得最不利内力条件位于纬度方向的位置变得不可预测。在加固设计计算中，甚至不可避免地必须涉及到许多风向才能与其他荷载相结合。本研究提出了一种虚拟均匀分布来代替实际的风效应不规则分布，避免了多风向的参与和整个纬度壳的计算，大大简化了设计计算程序。同时，简化程序得到的加香量仅为2%左右，分布更加合理。避免了多风向的参与和整个纬度壳的计算，大大简化了设计计算程序。同时，简化程序得到的加香量仅为2%左右，分布更加合理。避免了多风向的参与和整个纬度壳的计算，大大简化了设计计算程序。同时，简化程序得到的加香量仅为2%左右，分布更加合理。