A Promising Approach in the World: Tensile Structures Roofing

Year 2015, Volume: 7 Issue: 3, 2 - 6, 15.09.2015

Talha Ekmekyapar Alaa Tareq Al-shareef Derya Bakbak

https://doi.org/10.29137/umagd.379754

Abstract

Civil
engineering roof systems for outdoor environments find use in bazaars, car park
areas, outdoor sport facilities and places built to protect people or their
goods from environmental effects such as sun and heavy rain. Therefore, such
roofing systems have great amount of application and each country spends huge
volumes of materials to build these roof systems to improve life quality of
people in cities. Thus, it is evident that further research on these civil
engineering structures has the potential to decrease the cost of these roof
systems and build more efficient ones. Generally these roof systems are
manufactured employing structural steel material. As is well known, steel has
promising mechanical properties such as high strength and high stiffness which
can be exploited in structures that expected to receive very high magnitude of
loadings, such as earthquake resistant buildings. However, there also exist
some disadvantages of completely using steel in these roof systems. For
instance, due to unit weight of material the roofs manufactured using steel are
very heavy. So, construction process requires significant labour and time. Also
steel construction is an expensive process considering measure of covered area
for outdoor roof systems. Moreover, these kinds of roofs manufactured using
completely steel are not flexible in use, that is to say, when it is
unnecessary for some period of time it is not possible to remove the roof
covering and re-cover it when it is necessary again. This paper investigates a
novel concept in the world called as “tensile structures” used to cover wide
outdoor areas. This concept actually combines civil engineering designs and
some architectural aspects. Instead of using materials with high stiffness,
tensile structures adapt membrane materials to cover wide areas. Cable elements
accompany those membranes to transmit the internal forces and stresses to
structural columns or ground. Although membrane materials have lower strengths
compared to steel, these structures offer flexibility in use, light coverings,
lower costs and faster construction time. Since these structures are built
utilizing membrane materials and cables which support tension forces only,
conventional stress office methods are not capable of handling their analyses
and designs. Consequently, specific computational methods must be used to
perform such designs. In this paper special commercial software is used to
investigate behaviour of tensile structures. Three different configurations are
employed to cover a wide area. Structural analysis procedures of those
configurations are undertaken and stress distributions in membranes are
investigated. Discussions pertaining to motivation behind these structures,
load carrying capabilities and working principles are provided. Outcomes of
this study illustrate that these tensile structures have the potential to
replace some applications of steel roofs to lead lighter, flexible, low cost
and more aesthetic structures for outdoor environments.

Keywords

Tensile structures, outdoor roofing, structural mechanics

References

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• [4] D. Bakbak, ‘’Architectural Form Design and Structural Analysis of Tensile Structures’’, M.Sc. thesis, Department of Civil Engineering, Gaziantep University, Turkey, 2011.
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