Strength and rotational behaviour of composite beam-column connections KARL VAN DALEN A N D HERNAN G o~o y Qlreer~'\ U~~i\vzr.\ity. Kit~g\tori, Ol~t., Crrrrrrrlrr K7L 3N6 Rcccived Octobcr 5, I98 1 Rcviscd manuscript acceptcd Fcbruury 18. 1982Thc rcsults of an cxpcrimcntal study of thc strength and rotational ch:uactcristics of colnpositc stccl-concrctc bcam-column conncctions arc reported. Thrcc typcs ofconncction. flexible, scmi-rigid, and rigid. wcrc studictl. Spccimcns in which thc stecl clcments wcrc conncctcd in identical fashion wcrc tcstcd with no concrctc slab ant1 with a hcavily ant1 a lightly rcinforcctl compositc slab that was continuous around thc column.It was found that provision.of as littlc as 0.46% of the concrctc slab arca. as slab rcinforccmcnt continuing arountl the column, cnablcd a bcam-column conncction to dcvclop a rnomcnt of rcsistancc at lcast cclual to thc ultirnatc moment capacity of the associated compositc bc:um, cvcn whcn thc conncction bctwccn thc stccl clcmc~its thcmsclvcs had no significant moment carrying capacity. The rotational capacity of the composite beam-column conncctions was at lcast equal to that of a conventional nonconipositc rigid stccl conncction.Can. J. Civ. Eng.. 9, 313-322 (1982)

The rotational behaviour of clipped end plate connections was studied by subjecting nine clipped and three conventional or ''unclipped" specimens with varying connection geometry to combined shear and moment and obtaining the corresponding moment-rotation characteristics. It was found that thc clipped end plate connections in this investigation had more than adequate rotation capacity to permit an interior beam connected to a supporting member by this type of connection to achieve its full plastic moment, provided the length-to-depth ratio of the beam does not exceed 20. For the range of rotations that would be cxperienced by clipped end plate connections in a practical structure, a model originally developed to predict the moment-rotation behaviour of conventional shear end plate connections was modified so as to be applicable to clipped end plate connections. Good agreement was obtained between the test values and those predicted by the modified model. No adverse effect on the rotational behaviour of the connections was observed to result from the asymmetry caused by clipping the end plate.Le comportement des assemblages de plaque d'appui agrafCs soumis ii la rotation a CtC analysC en soumettant neuf Cchantillons agrafks ettrois tchantillons traditionnelsde gComCtrie diverse au cisaillement et au moment flCchissant afin d'obtenir les carac-tCristiques moment-rotation correspondants. On a constat6 que les assemblages de plaque d'appui agrafCs avaient une capacitC de rotation plus que suffisante pour permettre a une poutre intkrieure reliCe ii un ClCment porteur par ce type d'assemblage d'atteindre son moment plastique complet, pourvu que le rapport entre la longueur et la profondeur de la poutre ne soit pas supCrieur 5 20. Pour la gamme de rotations auxquelles seraient exposCs des assemblages de plaque d'appui agrafks dans une structure, un modkle d'abord mis au point pour prtdire le comportement moment-rotation d'assemblages de plaque d'appui traditionnels a Ct C modifit en fonction des assemblages de plaque d'appui agrafCs. On a obtenu une bonne similitude entre les valeurs d'essai et celles prCdites par le modtle modifit. L'asymCtrie qui rCsulte de l'application de cette solution n'a aucun effet nCgatif sur le comportement des assemblages soumis la rotation.

This paper examines the concept of enhancing the performance of timber connectors in truss joints by the introduction of transverse prestressing. The behaviour of lap splices of Douglas fir, with 63 mm split-ring connectors and end distances of 50, 100, 150, and 210 mm, was examined for various levels of prestress in a laboratory study. As well, the magnitude of the load that can be carried by the connection through friction between faying surfaces was also assessed for various levels of prestress. The simple technique used in the laboratory for introducing prestress is described. Results of the laboratory tests on 20 joint configurations are presented, and the experimentally determined strengths are compared with the calculated resistances using the provisions of CAN\CSA-086.1-M89 "Engineering design in wood (limit states design)." Key words: timber, connector, prestress, truss joint.

No abstract

An experimental program was undertaken to verify the end distance requirements in the Canadian standard for engineering design in wood for split ring connectors in joints loaded in compression. In a laboratory study, 48 joints of the Douglas fir-larch species group using 63 mm diameter split rings, 45 joints of the Douglas fir-larch species group using 102 mm diameter split rings, and 51 joints of the spruce-pine-fir species group using 63 mm diameter split rings were loaded to failure in compression. The split ring end distance varied between 50 and 200 mm for joints with 63 mm diameter split rings and between 80 and 220 mm for joints with 102 mm diameter split rings. Tests were also carried out to verify the cleavage strength of the wood and the strength of the wood in compression parallel-to-grain for each of the specimens. Results show that the end distance does not have any significant effect on the resistance of split ring connectors in joints with members loaded in compression. Key words: split ring, compression, end distance, timber, resistance.