Analysis of Behavior of Spatial Structures in Bridges Deck With Changes in Diameter and Length of Members

Document Type : Original Article

Authors

1 Department of Civil Engineering, Isfahan (Khorasgan) Branch, Islamic Azad University, Isfahan, Iran.

2 Department of Architecture, Mehr-Aeen Higher Education Institute, Bandar Anzali, Iran

10.22091/cer.2020.5328.1197

Abstract

The use of spatial structures despite the ease and speed of execution is always limited to covering the roofs with long spans. While these types of structures, which by their mechanism of load distribution to all members, have acceptable resistance to incoming loads, both dead and live, can be a good alternative for use in bridges deck. Therefore, in this paper, numerical modeling of a two-layered lattice spatial deck with different diameters and lengths of members, its behavior against dead and live loads caused by moving motor vehicles according to the AASHTO Code is investigated. The geometrical forming of the different topologies was performed using Formex algebra by Formian 2.0 software and numerical modeling of spatial decks using SAP2000 finite element software with linear static analysis. The results showed that with increasing the diameter of the members of the double-layered lattice deck from 13.94 to 19.37 cm, the cross-sectional area and consequently the stiffness of the members increase, which leads to an increase in the stiffness of the whole structure and as a result it leads to an increase in its resistance to dead loads due to the weight of the structure and to the moving loads due to the passage of motor vehicles. Also, with increasing the length of the members of the double-layered lattice deck from 1.5 to 4.5 meters, the distance between the nodes has increased and the number of nodes and members of the two layers, and their between which most of the elements of the whole structure are located at this distance has decreased, and consequently, it leads to a reduction in the dead loads of the structure and deflection due to these loads. On the other hand, because these nodes are selected from the joint type, which has freedom of movement in all directions, the reduction in the number of nodes leads to a relative decrease due to moving loads.

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References

[1] Chilton, J. (2000). Space grid structures. Architectural press.
[2] Shilin, D. O. N. G. (2009), “The development history, innovation, classification and practical application of spatial structures”, Spatial Structure, 15(3), 22–43.
[3] Shilin, D. O. N. G. (2010), “Development and expectation of spatial structures in China”, Journal of Build-ing Structures, 31(6), 38–51.
[4] Dong, S.L., Luo, Y.Z., & Zhao, Y. (2009). Analysis, design and construction of new space structure. China Architecture and Building Press, China.
[5] Liu, X.L. (2003). Modern space structures. Tianjing: Tianjing Univercity Press.
[6] Saitoh, M. (2006). Development and prospect of space structure— past, present, future of space structure design. Beijing: China Architecture and Building Press.
[7] Mei, J.K., Liu, D.M., & Yao, Y.X. (2002). Thinking of structure and construction of long-span structures. Beijing: China Architecture and Building Press.
[8] Ramaswamy, G. S., & Eekhout, M. (2002). Analysis, design and construction of steel space frames. Thom-as Telford.
[9] Taghizadeh, M. H., Behravesh, A., & Akbarlou, A. (2015). “Study on behavior of bridges deck built by spa-tial structures”, Journal of Structural and Construction Engineering, 2(1), 46-55.
[10] Dianat, P. (2014). “Use of space structures in seismic reinforcement of existing concrete structures”, the 4th National Conference on Spatial Structures, Tehran, May 19-20.
[11] Maalek, S., Maalek, R., & Maalek, B. (2014), “Largely neglected areas of application of skeletal space structures”, the 4th National Conference on Spatial Structures, May 19-20.
[12] Taghizadeh, M.H., & Behravesh, A. (2015), “Application of spatial structures in bridges deck”, Civil Engi-neering Journal, 1)1(, 1-8.
[13] Eskandar, H., & Maalek, S. (2016). “Investigation of technical and economic aspects of deck structure system of bridges deck consisting of two-layer mixed spatial grids in comparison with prefabricated post-tensioned concrete box-girder bridges”, the 9th International Congress on Civil Engineering, Mashhad, May 10-1.
[14] Taghizadeh Valdi, M. H., & Pourhadi Gavabari, M. (2020). “Analysis of spatial structures behavior in bridges deck with topology and layers changes”, Journal of Architecture, 2(13), 1-8.
[15] Vice presidency for Strategic Planning and Supervision, (2010). Code of practice for skeletal steel space structures of Iran, No 400.
[16] Nooshin, H. (1996), “A Technique for Surface Generation”, IASS Symposium, Stuttgart, Germany.
[17] Nooshin, H., & Moghimi, M. (2007), “Formex formulation of freeform structural surfaces”, 2nd National Conference on Space Structures, Tehran. Iran.
[18] Nooshin, H., & Disney, P.L. (2000), “Formex configuration processing I”, International Journal of Space Structures, 15(1), 1-52.
[19] Nooshin, H., & Disney, P.L. (2001), “Formex configuration processing II”, International Journal of Space Structures, 16(1), 1-56.
[20] Nooshin, H., & Disney, P.L. (2002), “Formex configuration processing III”, International Journal of Space Structures, 17(1), 1-50.
[21] Nooshin, H., Disney, P.L. & Champion, O.C. (1997). Computer-aided processing of polyhedric configura-tions. Chapter 12 in Beyond the Cube. Edited by J.F. Gabriel. John Wiley.
[22] Habibullah, A., & Wilson, E. (2005). General program of structures analysis and design SAP2000. Trans-lated by Afshin Torabi, and Reza Pashaei, 1st Edition, Simaye Danesh Publications.
[23] AASHTO LRFD. (2012). Bridge design specifications. 6th Edition.
[24] Baji, H., & Hashemi, S. J. (2005). Applied projects in computerized analysis and design of structures. 4th Edition, Motafakeran Publications.
[25] Tahooni, S. (2014). Design of steel structures (allowable stress method and limit state design - LRFD). 1st Edition, Elm va Adab Publications.
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Civil Infrastructure Researches
Volume 6, Issue 1 - Serial Number 10
September 2020
Pages 17-28

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