Investigation of Double-nuts and Sleeve Systems in Spherical Joints of Space Structures under Tensile and Compressive Forces

Ali Arjmandian¹ Seyed Mohammad Hossain Nouri Rahimabadi²

1) MSC. of Civil Eng. , Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran
2) Assistant Professor، Department of Mechanic, Shahr-e-Qods Branch, Islamic Azad University, Tehran, Iran , 09123787917,

IOI Code : XBKD-EZKAB
Publication : 3th. International Congress on Contemporary in Civil Engineering, Architecture and Urban Development(cautech.ir)
Abstract :
    Studies on spherical joints of space structures shows that most ruptures occur in tensile stresses, which is also due to the stiffness of the screw. Although other causes, such as human mistake, are also unaffected. The purpose of this paper is the comparison of two common systems in the spherical joints of space structures, the double-nuts and sleeve systems. The behavior of the screws in the tensile conection has been determined, numerical and experimental. The behavior of the sleeve under pressure has also been Investigated Numerical. For this purpose, a Sample of Double-nuts and Sleeve Systems screws have been tested and the ultimate resistance of each of the two systems has been determined the results of comparison of the two systems under tensile and compressive forces showed that the double nuts system performs better in both theoretical and experimental modes, up to 10% ultimate resistance and up to 60% nonlinear deformation.

Keywords : space structures spherical joints double nuts and sleeve systems screw