- Author
-
Lim, K. Y. S.
|
King, A. B.
- Title
- Protected Nailed Gusset Connections for Glulam Members. Study Report.
- Coporate
- Building Research Association of New Zealand, Judgeford
- Report
-
BRANZ Study Report SR29
1989
66 p.
- Keywords
-
timber
|
failure
|
fire resistance tests
|
gypsum
|
plasterboard
|
plywood
|
steels
|
structural design
|
temperature
- Identifiers
- deflections; glulam; gusset plates; joints; nailed connections; protal frames
- Abstract
- The fire performance of heavy gluded laminated (glulam) timber members based on the 'sacrificial method of char' is widely accepted. The performance of their mechanical connectors, possibly the weakest link, is frequently overlooked. This report describes the experimental testing of six full-size nailed moment-resisting gusset connections between glulam timber members when subjected to the 60 minutes (min) standard time temperature conditions. The parameters examined included different gusset types; different protection methods; beams of two depths, and two levels of applied load. The results of these indicated that protected nailed plywood or steel gusset connectons can achieve a 60 min Fire Resistance Rating (FRR). Protection using two layers of a gypsum based 'contro' board proved to be more than adequate, with a single layer achieving the 60 min FRR. The degree of protection offered by an intumescent coating on the steel gussets was inconclusive. This report also describes the experimental testing of four unloaded gusseted glulam specimens protected with a single layer of the 'control' board subjected to the 60 min standard time temperature conditions. These tests were carried out in a pilot furnace to determine the time temperature characteristics of the components beneth the protection, to enable a comparative test method to be developed.