In the last two decades, a number of efforts have been devoted to study the fire performance ofwood-wood-wood (WWW) and wood-steel-wood (WSW) connections. With the knowledge andexperimental data generated in those studies, attempts are being made in order to develop new calculationmethods and to improve design rules for timber connections in fire. The first part of this paper reviews thebehaviour of WWW and WSW connections under fire exposure. Existing fire-resistance test results,including failure time, failure mode, charring rate, effects of load ratio and member geometry aresummarized. The available calculation models are also discussed. In the second part, a new calculationmethod, given in a power-law relationship, is proposed for unprotected WWW and WSW connectionsbased on correlations using existing results. The effects of wood side member thickness, fastener diameterand load ratio are taken into account in the correlations. The new method is found to be quite accurate inpredicting the fire-resistance ratings of unprotected WWW and WSW connections using bolts and dowelsin both the ISO 834 and ASTM E119 standard fires. The validity of the proposed method covers timberconnections with a wide range of wood member thickness, fastener diameter, and load ratio. For protectedtimber connections using gypsum and plywood membranes, the component additive method is used toassess the fire-resistance ratings by adding the fire-resistance ratings of protective membranes to the fireresistanceratings of unprotected timber connections. Using the proposed calculation methods, designerswill be able to achieve the fire-resistance requirements for WWW and WSW connections by changing theside member thickness, bolt diameter and load ratio, or by applying additional protective membranesusing gypsum and plywood membranes.
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