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One of the best method to increase load bearing capacity and stiffness of reinforced concrete structures subjected to bending is the external prestressing with CFRP strips. Thanks to great mechanical parameters of CFRP strips and high efficiency of prestressing effects, this technology can be a good alternative to conventional strengthening methods and it has recent-ly been more often used for practical application. Tensioning of CFRP strips allows to increase load bearing capacity and stiffness of strengthened structural elements and enhances composite material utilisation in comparison with passive externally bonding technique. The first externally bonded prestressing system has been developed by Leonhardt, Andrä & Partners. This system is known as Sika Leoba

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Four-sided wind catchers are common examples of wind catchers in Yazd. Analysing the physical and structural features of these wind catchers can reveal part of the characteristics of traditional Iranian architecture and the ability of traditional architects to use such renewable energies as wind power. The present study attempts to examine the effect of the arrangement of main and accessory air-shaft partition walls on the structural behaviour and construction technology of four-sided wind catchers through conducting library and field research studies. The study also attempts to simulate the process of constructing a four-sided wind catcher based on an optimal type. The analyses indicate that in addition to the amount of air conditioning, the shape of the partition walls has a direct relationship with the wind catcher’s degree of resistance to the internal and external forces. Moreover, the extension of the partition walls into the entirety of the rack and canal, compared to other similar types with partition walls in the rack, are more resistant against the lateral forces and transfer their resultant pressure more consistently thanks to their connected and consistent structure. The analysis of the construction process of wind catchers revealed part of the characteristics of the traditional Iranian architecture, utilizing vernacular materials and aiming at constructing high structures that are efficient, resistant, and dependent on renewable wind energy.