Vol. 15, No. 4, pp. 398-405 (2019)
EXPERIMENTAL ANALYSIS OF SPACE TRUSSES WITH TYPICAL CONNECTIONS
REINFORCED WITH STEEL AND SISAL-RESIN SPACERS
Cleirton A. S. Freitas1,*, Welington V. Silva2, Luciano M. Bezerra2, Francisco F. S. M. Júnior1,
Vinícius C. P. Neto1, and Brenda A. T. Ribeiro1
1 Research Group on Structural Engineering in Cariri - GPEEC, Federal University of Cariri - http://www.ufca.edu.br, Juazeiro do Norte, Brazil
2 Department of Civil and Environmental Engineering, University of Brasilia - UnB http://www.unb.br, Brasília, Brazil
*(Corresponding author: E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.)
Received: 26 May 2019; Revised: 17 August 2019; Accepted: 01 September 2019
DOI:10.18057/IJASC.2019.15.4.10
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ABSTRACT
Space trusses are reticulate systems used worldwide because of their advantages in covering roofs with large free spaces. In addition to having a low cost, the self-weight of such trusses is relatively reduced. The limitations on the use of these structures are mainly related to the fragility of the nodes, specifically those classified as typical nodes which may collapse when submitted to service loads due to eccentricities generated by stamped connections. This fact restricts significantly the use of space trusses. Considering this fact, the present research evaluates a reinforcement proposal for the typical connections with a series of eighteen prototypes. The reinforcements tested are made with steel plates and spacers. In this work, spacers are made of steel or sisal with fiber polymer resin. Such spacers are employed to correct part of the eccentricities present at typical nodes. The experimental tests show an increase of about 40% of the resistant capacity of the truss with the proposed reinforcement avoiding the early collapse of typical nodes. In truss prototypes with typical nodes, local abrupt collapses always happened at nodes. In reinforced trusses, collapse took place by buckling of the bars at the top chord of the prototypes, therefore, taking account of the bar full resistance.
KEYWORDS
Space trusses, Fragility, Experimental study, Simple connections, Spacers reinforcement
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