近年来,我国冷却塔建设趋向于大型化(高度>190m)、由双/四塔简单群体组合向六/八塔复杂群体组合发展.风致干扰效应是冷却塔群结构设计的关键控制因素,但目前以风载荷为主导的冷却塔结构优化设计和研究多局限于上部结构塔筒本身,且仅针对规范二维对称风压分布作用,难以满足超大型冷却塔的发展建设需求.为评估上述效应对于结构设计安全和经济性能的影响,计入了冷却塔上、下部结构共同作用,筛选并推荐复杂群塔干扰条件多种不利载荷模式,逐一实施整体结构响应面和梯度搜索优化分析,汇总形成了综合考虑复杂载荷分布模式的冷却塔结构优化评估算法和策略.以典型冷却塔六塔组合布置为例,具体实施了考虑群塔组合下复杂风载荷分布模式影响的分阶段优化过程:采用同步测压风洞试验,研究了典型塔群组合的风致干扰效应,对比归纳出基于典型六塔组合的最不利风载荷分布模式及特征,而后将响应面法和梯度搜索法结合并引入冷却塔结构优化选型分析,同时兼顾冷却塔结构的安全性和稳定性,推荐了适用于多种风载荷作用模式的最优化冷却塔结构设计方案.%In recent years,cooling towers built in China tend to be of large-scale (>190m), and develop from simple combination with double or four towers to the more complex groups with six or eight towers.Wind-induced interference effects usually dominate the structural design of cooling tower group.However,the structural optimization design aiming at wind loads is mostly limited to the upper structures of cooling towers such as tower shells,and only considers two-dimensional symmetrical wind pressure distribution from the Chinese loading codes.So,it is rather difficult to meet the design requirements of the modern super-large cooling towers.In order to evaluate the influence of some key points mentioned above on the economical index of the whole structural design of the cooling towers,a large-scale hyperbolic cooling tower in six-tower combinations is taken as an example.Some of typical adverse load patterns under the complex interference conditions are firstly summarized using synchronous pressure measurement in wind tunnel test.For each adverse load pattern,the overall structure optimization is implemented by the hybrid algorithm involving response surface method and gradient search method.Then,the most optimized structural design of the cooling tower can be proposed by cross check through comparing these optimized results from series of the adverse wind load patterns,keeping the balance of structural economy and safety.
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