桁架拱轻钢塑料大棚抗风性能分析及结构参数优化

发布时间：2018-01-02 16:33

本文关键词：桁架拱轻钢塑料大棚抗风性能分析及结构参数优化　出处：《黑龙江八一农垦大学》2017年硕士论文　论文类型：学位论文

【摘要】：桁架拱轻钢塑料大棚因其具有结构简单、制作方便、维护费用低等优点,在我国北方寒区广泛使用。在塑料大棚快速发展的同时,不可避免地出现一些质量事故和安全问题,近年来因强风暴雪导致的大棚坍塌事件时有发生。截至目前,我国没有明确针对温室结构的相关荷载规范,这使得大棚建造时缺少设计依据,大棚设计制造不规范。现行温室结构设计重点是温室形状及尺寸,对安全性及耐久性规定较少。多数塑料大棚由秧棚生产厂家设计并制作,形式五花八门,质量良莠不齐。针对塑料大棚量大面广又常发生破坏的现状,本文在对大庆市拱形塑料大棚充分调查的基础上,分析了已建成大棚的建设现状及存在问题,建立了桁架拱轻钢塑料大棚有限元模型,计算了风荷载作用下大棚骨架的应力及位移,对桁架拱轻钢塑料大棚骨架参数进行了优化设计。具体工作如下所示:(1)对大庆市拱形塑料大棚进行了现场调查工作,得到大庆市已建成拱形塑料大棚的结构类型、建设现状及存在问题。(2)利用ANSYS有限元计算软件建立了大庆市有代表性的桁架拱轻钢塑料大棚骨架平面内模型,通过结构力学求解器对桁架拱轻钢塑料大棚骨架在面内风荷载标准值下的应力及位移计算结果与有限元计算结果对比,二者吻合较好,说明利用有限元计算大棚骨架模型受力是可靠的。(3)采用ANSYS有限元计算模型分析了桁架拱轻钢塑料大棚骨架模型在面内风荷载设计值下的应力及风荷载标准值下的位移。计算结果表明,除在10年一遇风荷载作用下跨度为6m、8m、10m以及12m大棚骨架位移不超过允许值外,在10年一遇风荷载作用下大棚骨架应力及30年一遇、50年一遇风荷载作用下大棚骨架位移与应力均超过允许值,不能保证安全。(4)利用有限元优化程序,对桁架拱轻钢塑料大棚进行结构参数优化设计,主要优化变量为大棚上弦杆、下弦杆及中间腹杆的截面直径和壁厚。在保证大棚骨架最大应力及X向位移和Y向位移均不超过允许值的条件下,使大棚骨架总用钢量达到最少,提出设计建议。
[Abstract]:Because of the light steel truss arch plastic greenhouse has the advantages of simple structure, convenient manufacture, maintenance and low cost, widely used in northern cold regions in China. The rapid development in plastic greenhouse. At the same time, inevitably some quality accidents and safety issues in recent years because of the strong storm snow caused by greenhouse collapse occur. As of now, I according to the relevant specification's no definite load of greenhouse structure, which makes the greenhouse construction lack of design basis, design and manufacture of greenhouse is not standardized. The current greenhouse structure design is focused on greenhouse shape and size, less on safety and durability requirements. Most of the plastic greenhouse by seedling shed manufacturers to design and manufacture, all kinds of forms, quality is uneven in quality. According to the present situation of plastic greenhouse in the wide and often destroyed, based on the full investigation of Daqing arch plastic greenhouse, the analysis has been built The present situation of the construction of the greenhouse and the existing problems, a steel truss arch plastic finite element model, the stress and displacement under the wind load calculation of tunnel frame, steel truss arch plastic greenhouse frame parameters were optimized. The specific work is as follows: (1) conducted a field investigation in Daqing city. Plastic greenhouse, Daqing city has built arch plastic greenhouse structure, the construction of the status quo and existing problems. (2) established a Daqing representative steel truss arch plastic greenhouse skeleton plane model using ANSYS finite element software, the structural mechanics solver of steel truss arch plastic greenhouse skeleton in the wind standard value of load stress and displacement calculation results with finite element calculation results, two good agreement, indicating that the calculation model of greenhouse skeleton stress is reliable by using the finite element (3) by ANS. YS finite element calculation model of steel truss arch plastic greenhouse skeleton model in the design of surface wind load under the stress and the displacement under the wind load standard value. The calculation results show that, except in 10 years under the wind load span is 6m, 8m, 10m and 12m in skeleton displacement does not exceed the allowable value of foreign in 10 years, under the wind load of greenhouse skeleton stress and in 30 years, 50 years under the wind load of greenhouse skeleton displacement and stress are more than the allowable value, can not guarantee the security. (4) by using the finite element optimization program of steel truss arch plastic greenhouse structure parameter optimization, the main optimization variables as in the top chord of the bottom chord, and the middle truss section diameter and wall thickness. The greenhouse skeleton of maximum stress and displacement in X direction and Y direction displacement does not exceed the allowable value under the condition that the total amount of steel skeleton of greenhouse is minimal, and presents a Design Suggestion.

【学位授予单位】：黑龙江八一农垦大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：S625.1

【相似文献】