折叠网格结构的几何构成及其力学性能研究
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摘要
折叠结构是20世纪六十年代发展起来的一种新型空间结构,该结构用时展开、不用时可折叠收起。折叠结构由于折叠后体积小、展开方便,而日益受到重视,并逐渐应用于建筑和航天领域。但在建筑领域的工程应用在国内还很少见,有必要展开相关研究。本文所研究的折叠网格(包括折叠网架、网壳)结构是建筑领域里比较常见的折叠结构形式,多用于临时性或半永久性建筑。
折叠结构设计包括折展过程的几何设计和展开定位后的受荷分析两部分,其中几何设计是结构设计的基础。为此,本文首先对折叠网格结构的几何构成进行了研究。几何设计的主要内容,对于外加锁式折叠结构(本文研究),是保证结构(此时实质上为机构)能够自由折展。通过对折叠结构的基本单元——三剪杆剪铰单元的几何性质进行研究,推导了多种剪铰单元的几何性质以及保证结构折展性能的几何限制条件,并将具体的剪铰单元运用到折叠网架、网壳结构中去。在ANSYS里对几种具体的折叠网架、网壳的折展过程进行了动态模拟,论证了其可展性。
折叠结构展开成形后的力学性能也是本文研究的主要内容。通过大量算例分析,总结了网格高度、网格尺寸大小变化对结构力学性能的影响规律。由于剪式铰单元的特性,折叠网格结构主要依靠杆件的弯曲应力来抵抗外荷载弯矩,致使结构的刚度较差。借鉴普通网架、网壳的受力机理,对各种形式折叠网架、网壳加上弦杆或下弦杆或同时加上下弦杆,分析它们对结构力学性能的影响规律,通过分析比较,对各种结构提出合理的改进方案,以运用到工程实际。
本文最后总结了折叠结构的各种节点形式,分析它们的优缺点,以便更好地运用到实践中。
The foldable structure, developed in the 1960s, is a new style of space structures. The proposed structure is unfolded when used, and it can be put away after folded while not used. As a result of its small volume after folded and its convenience when unfolded, the structure, to which the growing attention is being paid, is applied gradually in the field of architecture and astronautics.However, its application in the field of architecture is still rare in our country, so the correlated study is to be performed essentially. The foldable latticed structure (including foldable latticed plate and foldable dome) studied in the paper is one of quite common styles in the field of architecture, and is often adopted in temporary or semi-permanent structures.
The design of foldable structure includes geometrical design of folding procession and loading analysis after unfolded localization, and the geometrical design is the basis of structure design. Based on this, the geometrical constitution of foldable latticed structure is firstly studied in this paper. The geometrical design, for manual-locking foldable structure, is to ensure that the structure (it is a mechanism essentially) is folded and unfolded freely. According to the study on the geometrical behavior of the basic element of foldable structure--scissor-like element with 3 scissor-like rods, gain the geometrical behavior and geometrical restrained qualification of several kinds of scissor-like elements is educed, additionally, concrete scissor-like elements is used in foldable latticed plates and foldable domes. Resorting to ANSYS, the dynamic simulation is conducted to simulate the folding process of several foldable plates and shells, and the outspread capability is validified.
The mechanical performance is also mainly studied in the paper. Based on mounts of calculation and analysis, the rule that structural mechanical performance varies with the changing of the hight and size of the lattices is concluded. Due to the performance of scissor-like elements, the foldable structure mainly relies on bending stress of pole elements to resist bending moment of external load, which results in the poor rigidity of the structure. Taking mechanical performance of common latticed plate and shell for reference, either upper chords or lower chords, or both of them are added in various types of foldable latticed plates and foldable shells, the rule that they affect the structural mechanical performances is analyzed. According to the analysis, the reasonable and improved scheme is put forward for varieties of structures, so as to be used in engineering practice.
At last, various styles of joints of foldable structure are summarized; their advantages and disadvantages are discussed, in order that the foldable structure could be applied in practice better.
折叠结构设计包括折展过程的几何设计和展开定位后的受荷分析两部分,其中几何设计是结构设计的基础。为此,本文首先对折叠网格结构的几何构成进行了研究。几何设计的主要内容,对于外加锁式折叠结构(本文研究),是保证结构(此时实质上为机构)能够自由折展。通过对折叠结构的基本单元——三剪杆剪铰单元的几何性质进行研究,推导了多种剪铰单元的几何性质以及保证结构折展性能的几何限制条件,并将具体的剪铰单元运用到折叠网架、网壳结构中去。在ANSYS里对几种具体的折叠网架、网壳的折展过程进行了动态模拟,论证了其可展性。
折叠结构展开成形后的力学性能也是本文研究的主要内容。通过大量算例分析,总结了网格高度、网格尺寸大小变化对结构力学性能的影响规律。由于剪式铰单元的特性,折叠网格结构主要依靠杆件的弯曲应力来抵抗外荷载弯矩,致使结构的刚度较差。借鉴普通网架、网壳的受力机理,对各种形式折叠网架、网壳加上弦杆或下弦杆或同时加上下弦杆,分析它们对结构力学性能的影响规律,通过分析比较,对各种结构提出合理的改进方案,以运用到工程实际。
本文最后总结了折叠结构的各种节点形式,分析它们的优缺点,以便更好地运用到实践中。
The foldable structure, developed in the 1960s, is a new style of space structures. The proposed structure is unfolded when used, and it can be put away after folded while not used. As a result of its small volume after folded and its convenience when unfolded, the structure, to which the growing attention is being paid, is applied gradually in the field of architecture and astronautics.However, its application in the field of architecture is still rare in our country, so the correlated study is to be performed essentially. The foldable latticed structure (including foldable latticed plate and foldable dome) studied in the paper is one of quite common styles in the field of architecture, and is often adopted in temporary or semi-permanent structures.
The design of foldable structure includes geometrical design of folding procession and loading analysis after unfolded localization, and the geometrical design is the basis of structure design. Based on this, the geometrical constitution of foldable latticed structure is firstly studied in this paper. The geometrical design, for manual-locking foldable structure, is to ensure that the structure (it is a mechanism essentially) is folded and unfolded freely. According to the study on the geometrical behavior of the basic element of foldable structure--scissor-like element with 3 scissor-like rods, gain the geometrical behavior and geometrical restrained qualification of several kinds of scissor-like elements is educed, additionally, concrete scissor-like elements is used in foldable latticed plates and foldable domes. Resorting to ANSYS, the dynamic simulation is conducted to simulate the folding process of several foldable plates and shells, and the outspread capability is validified.
The mechanical performance is also mainly studied in the paper. Based on mounts of calculation and analysis, the rule that structural mechanical performance varies with the changing of the hight and size of the lattices is concluded. Due to the performance of scissor-like elements, the foldable structure mainly relies on bending stress of pole elements to resist bending moment of external load, which results in the poor rigidity of the structure. Taking mechanical performance of common latticed plate and shell for reference, either upper chords or lower chords, or both of them are added in various types of foldable latticed plates and foldable shells, the rule that they affect the structural mechanical performances is analyzed. According to the analysis, the reasonable and improved scheme is put forward for varieties of structures, so as to be used in engineering practice.
At last, various styles of joints of foldable structure are summarized; their advantages and disadvantages are discussed, in order that the foldable structure could be applied in practice better.
引文
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3 C.J. Gantes. Deployable Structures: Analysis and Design. WIT Press.2000:1~291
4 S.Pellegrino, S.D.Guest. IUTAM-IASS Symposium on Deployable Structures: Theory and Applications. Cambridge, U.K. 1998:1~197
5 R.E. Freeland. Survey of Deployable Antenna Concepts-Large Space Antenna Systems Technology. NASA-2269, Part I, 1983:381~421
6 M. Chew, P. Kumar. Conceptual Design of Deployable Space Structures form the Viewpoint of Symmetry. International Journal of Space Structures. 1993, 8(1&2):17~27
7 J.M. Hedgepeth. Influence of Fabrication Tolerances on the Surface Accuracy of Large Antenna Structures. AIAA Journal. 1982, 20(5): 6840~6856
8刘晓峰,谭惠丰,杜星文.充气太空结构及其展开模拟研究.哈尔滨工业大学学报. 2004,36(4):508~512
9王泽云,苏晓韵.可展空间索杆结构展开过程的仿真计算.四川建筑科学研究. 2005, 31(3): 10~13
10 H. Tsunoda, Y. Senbokuya. Deployment Characteristics of Rigidizable Space Inflatable Structures. Space Technology. 2003, 23(2&3): 119-129
11薛素铎,刘景园.可展开折叠式空间结构的研究现状与展望.第三届全国结构工程学术会议论文集. 1994: 1402~1405
12 C.J. Gantes, R.D. Logcher, J.J. Connor, Y. Rosenfeld. Deployability Conditions for Curved and Flat, Polygonal and Trapezoidal DeployableStructures. International Journal of Space Structures. 1993,8(1&2): 97~106
13 Gantes, C.J., Konitopoulou, E., curvature. In: Proceedings of UK.Snap-through-type deployable structures with arbitrary curvature. In: Proceedingsof the 5th International Conference on Space Structures, Surrey, UK.
14 Gantes, C.J.. An improved analytical model for the prediction of the nonlinear behavior of flat and curved deployable spaceframes. Journal of Constructional Steel Research, 1997, 44 (1-2): 129 ~158.
15 Gantes, C.J., Connor, J.J., Logcher, R.D.. A systematic design methodology for deployable structures.International Journal of Space Structures, 1994, 9 (2): 67 ~86.
16 Y. Rosenfeld, Y. Ben-Ami, R.D. Logcher. A Prototype“Clicking”Scissor-Link Deployable Structure. Int. J. of Space Structures. 1993,8(1&2):85~95.
17 C.J. Gantes. A Simple Friction Model for Scissor-type Mobile Structures. Journal of Engineering Mechanics, ASCE. 1993, 119(3):456~475.
18 M. Ebara, K. Kawaguchi. Foldable Rigid Connections. IUTAM-IASSSymposium on Deployable Structures: Theory and Applications. 2000:97~105.
19 S. El-Lishani, H. Nooshin, P. Disney. Investigating the Statical Stability of Pin-jointed Structures Using Genetic Algorithm. Int. J. of Space Structures. 2005, 20(1):53~68.
20 F. Escrig, J.P. Valcarcel. Geometry of Expandable Space Structures. Int. J. of Space Structure. 1993, 8(1&2):71~82.
21 J. Morales, J. Sanchez, F. Escrig. Geometry of Deployable Structures Generated by Computer-aided Design. In: Mobile and Rapidly Assembled StructuresⅡ. Computational Mechanics Publications. 1996:253~258.
22 Y. Chen, Z. You. Deployable Structures Based on the Bricard Linkages. Collection of Technical Papers-AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference. 2004, 2:997~1003.
23 C.J. Gantes, E. Konitopoulou. Geometric Design of Arbitrarily Curved Bi-stable Deployable Arches with Discrete Joint Size. International Journal of Solids and Structures. 2004, 41(20):5517~5540.
24 J.P. Valcarcel, F. Escrig. Recent Advance in the Analysis of Expandable Structure. In: Mobile and Rapidly Assembled StructuresⅡ. Computational Mechanics Publications. 1996:45~54.
25 J. Sanchez, F. Escrig, J.P. Valcarcel. Analysis of Reduced Scale Models of Xfranes Structures. In: Mobile and Rapidly Assembled StructuresⅡ.Computational Mechanics Publications. 1996:55~62.
26 J. Sanchez, F. Escrig, J.P. Valcarcel. The Adventure of Covering a Swimming-Pool with an X-frame Structure. In: Mobile and Rapidly Assembled StructuresⅡ. Computational Mechanics Publications. 1996:113~122.
27钱志伟,程万海,刘锡良.折叠结构的受力分析.建筑结构学报. 1996, 17(2):48~57.
28刘锡良,朱海涛.折叠网架动力特性研究.建筑结构学报.1999, 20(5):66~69.
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31罗尧治,胡宁,沈雁彬,董石麟.网壳结构“折叠展开式”计算机同步控制整体提升施工技术.建筑钢结构进展. 2005, 7(4):27~32.
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33李源,殷继刚,闫文魁,颜卫亨.折叠网架轴心受压铝合金杆件的稳定系数.工业建筑. 2005, 35(s):357~359.
34陈向阳,关富玲.折叠结构几何非线性分析.计算力学学报. 2000, 17(4):435~440.
35岳建如,关富玲等.可展构架式抛物面天线背架模型设计.工程设计. 2000, (2):32~37.
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38陈向阳,关富玲,陈务军.折叠结构的主从自由度分析.工程力学. 1999, (5): 83~88.
39陈向阳,关富玲.折叠结构几何非线性分析.计算力学学报. 2000, 17(4):435~440.
40赵孟良,吴开成,关富玲.空间可展桁架结构动力学分析.浙江大学学报. 2005, 39(11):1669~1674.
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2 F. Escrig. General Surney of Deployability in Architecture. In: Mobile and Rapidly Assembled StructuresⅢ. WIT Press. 2000:3~22
3 C.J. Gantes. Deployable Structures: Analysis and Design. WIT Press.2000:1~291
4 S.Pellegrino, S.D.Guest. IUTAM-IASS Symposium on Deployable Structures: Theory and Applications. Cambridge, U.K. 1998:1~197
5 R.E. Freeland. Survey of Deployable Antenna Concepts-Large Space Antenna Systems Technology. NASA-2269, Part I, 1983:381~421
6 M. Chew, P. Kumar. Conceptual Design of Deployable Space Structures form the Viewpoint of Symmetry. International Journal of Space Structures. 1993, 8(1&2):17~27
7 J.M. Hedgepeth. Influence of Fabrication Tolerances on the Surface Accuracy of Large Antenna Structures. AIAA Journal. 1982, 20(5): 6840~6856
8刘晓峰,谭惠丰,杜星文.充气太空结构及其展开模拟研究.哈尔滨工业大学学报. 2004,36(4):508~512
9王泽云,苏晓韵.可展空间索杆结构展开过程的仿真计算.四川建筑科学研究. 2005, 31(3): 10~13
10 H. Tsunoda, Y. Senbokuya. Deployment Characteristics of Rigidizable Space Inflatable Structures. Space Technology. 2003, 23(2&3): 119-129
11薛素铎,刘景园.可展开折叠式空间结构的研究现状与展望.第三届全国结构工程学术会议论文集. 1994: 1402~1405
12 C.J. Gantes, R.D. Logcher, J.J. Connor, Y. Rosenfeld. Deployability Conditions for Curved and Flat, Polygonal and Trapezoidal DeployableStructures. International Journal of Space Structures. 1993,8(1&2): 97~106
13 Gantes, C.J., Konitopoulou, E., curvature. In: Proceedings of UK.Snap-through-type deployable structures with arbitrary curvature. In: Proceedingsof the 5th International Conference on Space Structures, Surrey, UK.
14 Gantes, C.J.. An improved analytical model for the prediction of the nonlinear behavior of flat and curved deployable spaceframes. Journal of Constructional Steel Research, 1997, 44 (1-2): 129 ~158.
15 Gantes, C.J., Connor, J.J., Logcher, R.D.. A systematic design methodology for deployable structures.International Journal of Space Structures, 1994, 9 (2): 67 ~86.
16 Y. Rosenfeld, Y. Ben-Ami, R.D. Logcher. A Prototype“Clicking”Scissor-Link Deployable Structure. Int. J. of Space Structures. 1993,8(1&2):85~95.
17 C.J. Gantes. A Simple Friction Model for Scissor-type Mobile Structures. Journal of Engineering Mechanics, ASCE. 1993, 119(3):456~475.
18 M. Ebara, K. Kawaguchi. Foldable Rigid Connections. IUTAM-IASSSymposium on Deployable Structures: Theory and Applications. 2000:97~105.
19 S. El-Lishani, H. Nooshin, P. Disney. Investigating the Statical Stability of Pin-jointed Structures Using Genetic Algorithm. Int. J. of Space Structures. 2005, 20(1):53~68.
20 F. Escrig, J.P. Valcarcel. Geometry of Expandable Space Structures. Int. J. of Space Structure. 1993, 8(1&2):71~82.
21 J. Morales, J. Sanchez, F. Escrig. Geometry of Deployable Structures Generated by Computer-aided Design. In: Mobile and Rapidly Assembled StructuresⅡ. Computational Mechanics Publications. 1996:253~258.
22 Y. Chen, Z. You. Deployable Structures Based on the Bricard Linkages. Collection of Technical Papers-AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference. 2004, 2:997~1003.
23 C.J. Gantes, E. Konitopoulou. Geometric Design of Arbitrarily Curved Bi-stable Deployable Arches with Discrete Joint Size. International Journal of Solids and Structures. 2004, 41(20):5517~5540.
24 J.P. Valcarcel, F. Escrig. Recent Advance in the Analysis of Expandable Structure. In: Mobile and Rapidly Assembled StructuresⅡ. Computational Mechanics Publications. 1996:45~54.
25 J. Sanchez, F. Escrig, J.P. Valcarcel. Analysis of Reduced Scale Models of Xfranes Structures. In: Mobile and Rapidly Assembled StructuresⅡ.Computational Mechanics Publications. 1996:55~62.
26 J. Sanchez, F. Escrig, J.P. Valcarcel. The Adventure of Covering a Swimming-Pool with an X-frame Structure. In: Mobile and Rapidly Assembled StructuresⅡ. Computational Mechanics Publications. 1996:113~122.
27钱志伟,程万海,刘锡良.折叠结构的受力分析.建筑结构学报. 1996, 17(2):48~57.
28刘锡良,朱海涛.折叠网架动力特性研究.建筑结构学报.1999, 20(5):66~69.
29计飞翔.折叠结构体系及结构静力性能研究.西安:长安大学硕士学位论文. 2005: 1~49.
30向华.折叠式网壳帐篷结构的足尺试验研究.西安:长安大学硕士学位论文. 2004: 1~67.
31罗尧治,胡宁,沈雁彬,董石麟.网壳结构“折叠展开式”计算机同步控制整体提升施工技术.建筑钢结构进展. 2005, 7(4):27~32.
32缪炳祺,曲广吉,杨雷,刘银虎.折叠式桁架机构展收运动动力学建模和分析.中国空间科学技术. 2004(1):1~6.
33李源,殷继刚,闫文魁,颜卫亨.折叠网架轴心受压铝合金杆件的稳定系数.工业建筑. 2005, 35(s):357~359.
34陈向阳,关富玲.折叠结构几何非线性分析.计算力学学报. 2000, 17(4):435~440.
35岳建如,关富玲等.可展构架式抛物面天线背架模型设计.工程设计. 2000, (2):32~37.
36陈务军,关富玲等.空间可展开桁架结构展开过程分析的理论与方法.浙江大学学报(工学版). 2000, 34(4):382~387.
37胡其彪,关富玲等.一种新型展开/折叠式空间伸展臂结构方案的设计研究.工程设计. 1999, (4):36~40.
38陈向阳,关富玲,陈务军.折叠结构的主从自由度分析.工程力学. 1999, (5): 83~88.
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