Thin Steel Rings as a Feasible Alternative to Connect Bamboo Culms


Thin Steel Rings as a Feasible Alternative to Connect Bamboo Culms

J.J. García, C. Benítez, L. Villegas, R. Morán

Abstract. Bamboo is highlighted by its high axial strength, lightness, tubular shape and high sustainability. Bamboo connections cannot be easily built due to the hollow cylindrical shape and the high dimensional variation and transverse weakness of the culms, which tend to fail by longitudinal splitting. Joints recommended by the Colombian construction code use bolts, curved cuts and mortar injection to increase the transverse strength. These joints require high labor intervention and cannot be used in massive projects using prefabricated processes. We explore the use of thin steel semi-rings to connect bamboo culms. As the rings (formed with two semi-rings) are thin enough they can conform to the irregularities of the culm after being tighten. Thus, the ring applies an external pressure to the culm and creates a compressive circumferential stress distribution, which counteracts the creation of longitudinal splits. Moreover, even after initial fissures the ring avoids the separation of the parts, which generates ductile modes of failure. We performed experiments of Guadua angustifolia culms wrapped with steel rings under axial and transverse loading. Axial experiments showed maximum loads in the range 7500-18000 N with signs of high plastic deformations that usually begin at around 5000 N. Experiments under transverse loading showed maximum loads in the range 12000-20000 N with ductile types of failure.

Guadua Angustifolia, Bamboo Joints, Steel Rings

Published online , 10 pages
Copyright © 2018 by the author(s)
Published under license by Materials Research Forum LLC., Millersville PA, USA

Citation: J.J. García, C. Benítez, L. Villegas, R. Morán, ‘Thin Steel Rings as a Feasible Alternative to Connect Bamboo Culms’, Materials Research Proceedings, Vol. 7, pp 661-670, 2018


The article was published as article 63 of the book Non-Conventional Materials and Technologies

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