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    闫冬梅, 胡林, 周长吉, 闫俊月. 椭圆管单管拱架日光温室结构性能分析[J]. 农业工程学报, 2022, 38(5): 217-224. DOI: 10.11975/j.issn.1002-6819.2022.05.026
    引用本文: 闫冬梅, 胡林, 周长吉, 闫俊月. 椭圆管单管拱架日光温室结构性能分析[J]. 农业工程学报, 2022, 38(5): 217-224. DOI: 10.11975/j.issn.1002-6819.2022.05.026
    Yan Dongmei, Hu Lin, Zhou Changji, Yan Junyue. Analysis of the performance of the oval tube arch of single-tube solar greenhouses[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2022, 38(5): 217-224. DOI: 10.11975/j.issn.1002-6819.2022.05.026
    Citation: Yan Dongmei, Hu Lin, Zhou Changji, Yan Junyue. Analysis of the performance of the oval tube arch of single-tube solar greenhouses[J]. Transactions of the Chinese Society of Agricultural Engineering (Transactions of the CSAE), 2022, 38(5): 217-224. DOI: 10.11975/j.issn.1002-6819.2022.05.026

    椭圆管单管拱架日光温室结构性能分析

    Analysis of the performance of the oval tube arch of single-tube solar greenhouses

    • 摘要: 为探明椭圆管单管拱架日光温室的结构性能,该研究以北京地区风雪荷载为例,选取8、9、10 m三种常见跨度的日光温室为研究对象,依据国家标准《农业温室结构荷载规范》和农业行业标准《日光温室设计规范》确定日光温室的建筑剖面尺寸以及荷载作用形式,主要研究日光温室在屋脊不同位置设置拉杆时,随着拉杆位置的不同,在保证结构安全的前提下,针对拱架两端与基础和后墙的不同连接形式、不同跨度以及不同的屋脊形式建立结构计算模型,运用3D3S软件计算分析拉杆设置位置的变化对单管拱架的内力影响。计算发现,不论拱架与后墙采用哪种连接形式,当拱架与基础采用固接时,设置拉杆时拱架的应力比系数最小为0.974,其余均大于1.0,此种连接形式都应避免设置拉杆;当拱架与基础采用铰接时,设置拉杆时拱架的应力比系数大部分小于1.0,应尽量增设拉杆;在拱架与基础采用铰接连接、与后墙采用固结连接时,不同跨度日光温室增设屋脊拉杆的作用效果呈现曲线变化态势,9 m跨度的日光温室设置拉杆后的应力比系数最小,为0.90,因此推荐温室的跨度以9 m为宜;对尖屋脊和圆弧屋脊日光温室拱架的内力分析发现,建议如果不设屋脊拉杆,温室的屋脊形式应尽量做成圆弧形,而设置屋脊拉杆后可将屋脊做成尖屋脊。该研究成果可为椭圆管单管拱架日光温室的结构设计提供理论支撑。

       

      Abstract: Less shading of the steel skeleton has been the dominant structure of the Chinese solar greenhouse in recent years, due to the light structure of the single-tube arch center. The disciform arch center can hold more sections of the component, indicating the stronger carrying capacity in the same amount of steel, compares with the circular tube. Furthermore, the disciform arch center is a closed structure, compare with type C steel. The components shared a much stronger resistance to deformation. The disciform tube can be in the single arch center popular material, particularly for the current greenhouse with the light assemble structure. In this study, three groups were selected in the common spans of 8, 9, and 10m for the snow load in the Beijing region. The section size of the greenhouse and the form of load action was selected, according to the "Code for the design load of horticultural greenhouse structures" and "Code for the design of Chinese solar greenhouse". The cross-sectional dimensions of the Chinese solar greenhouse with three spans were 100 mm?40 mm?5 mm, 100 mm? 40 mm?2.5 mm, 110 mm?40 mm?2.5 mm, where the flat oval pipe was used as the load-bearing arch. The spacing between the skeletons was 1.0 m, and the longitudinal support was adopted as a circular tube of φ25 mm×1.5 mm. The material of the skeleton was the ordinary carbon structural steel Q235. The design life of the Chinese solar greenhouse was considered as 10 years. Permanent loads were generated by the arches and permanent equipment, whereas, the variable loads mainly included a load of crop, snow, wind, roof live, and thermal insulation. The building was set as four types of attachment (consolidation with consolidation, hinge with hinge, consolidation with hinge, and hinge with consolidation), three types of span (8, 9, and 10 m), and two kinds of roof form (sharp roof ridge and round roof ridge), where the straining beam was set in different positions. A computational model was established to determine the influence of straining beam position on the single-tube arch center axial force, bending moment, and maximum stress ratio. The software (3D3S) was selected for the modeling operation in a wide range of applications for the rhino curve. The modeling accuracy was improved to import any section form. If the arch center was connected with the back wall, whatever the kind of attended mode, the straining beam was avoided, when the arch center connected with the base used the solid connection. When the arch center connected with the base used the hinge joint, the straining beam was set. In four connection modes, the stress ratio of the arch frame was the largest, which was hinged with the foundation and the back wall. The stress ratio of the arch frame was the smallest, which was hinged with the foundation and consolidated with the back wall. The connection between the arch and the foundation was hinged to consolidate the connection with the back wall in the engineering design. In this case, the tie rod was set more effectively. The roof straining beam presented the curve in the greenhouse with the different spans, when the arch center connected with the base use hinges, or with the backwall use hinges. The structural bearing force was required the greenhouse span of 9 m. Consequently, the roof form was a round arc without a straining beam, otherwise, the roof can be sharp with the straining beam. The findings can provide the theoretical support to design the oval-tube arch center of a single-tube Chinese solar greenhouse.

       

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