双层双曲线网壳结构冷却塔温度应力的研究

把双层双曲线网壳结构竖向应用于冷却塔的筒壁 ,在网壳的周围挂金属面板 ,筒壁放在底部环梁上 ,形成了上面为网壳结构 ,下面为钢筋混凝土结构的新型结构。考虑双层双曲线网壳结构冷却塔由于均匀温度场变化 ,导致筒壁内外的温差 ,产生温度应力。并且结合边界约束条件的影响来探讨该结构的温度应力。分析了冷却塔杆件在均匀温度场变化下 ,由于不能自由地热胀冷缩 ,而产生了温度应力 ,同时给出了分析方法。并且根据有限元理论 ,用VisualBasic编制了温度应力分析程序。针对具体的工程实例探讨温度应力在边界的法线方向 ,约束条件分别为固定、弹性、放松三种情况下杆件温度应力的变化规律 ,给出了一些对网壳结构冷却塔设计有参考价值的结论和建议

THE RESEARCH ON TEMPERATURE STRESS OF COOLER TOWER OF DOUBLE HYPERBOLIC RETICULATED SHELL

The latticed shell of double-layer hyperbolic pyramid is vertically applied to the structure of cooling tower and reinforced concrete plates with ribs are put up around the latticed shell,a kind of new construction that includes the lower reinforced concrete structure and the upper latticed shell structure is established.Temperature stress is caused due to a reduction of temperature between inside and outside,in the condition of working of cooling tower of the double hyperbolic reticulated shell or sunning temperature stress of cooling tower is discussed based on different boundary restraint conditions.The paper points out that members can't freely expand with heat and extract with cold,temperature stress can produce on the conditions of changing temperature range,at the same time an analytic method is introduced.By the finite element theory and VB6.0 advanced programming language,a program of temperature stress analysis of cooling tower is programmed.By way of specific project,the changing law of temperature stress of the members is reported,after centricity of boundary restraint conditions of elasticity or fixing or freeness.Finally,some valuable conclusions and suggestions have been given for guiding the design of cooling tower of reticulated shell.