Allowable stresses depend on species, moisture and duration of load.
Allowable stresses vary with species grade, moisture, load duration and size; adjustment factors for creep and stability. Members: joists, studs, trusses, glulam beams. Connections (nails, bolts, plates) usually govern; protect against decay and fire.
A timber floor joist 50×200 at 400 mm spacing spans about 4 m.
Timber strength depends on species, grade, moisture and load duration, so timber design uses adjustment factors to reflect these effects.
Allowable stresses depend on species, moisture and duration of load.
Timber strength depends on species, grade, moisture and load duration, so timber design uses adjustment factors to reflect these effects.
Timber can carry higher short-term loads than long-term loads, so codes reduce allowable stress for permanent loads.
Products such as glulam, laminated veneer lumber and cross-laminated timber, which give predictable strength and larger sizes than solid timber.
Typical applications include designing a timber floor joist for a domestic building, choosing a glued laminated beam for a long-span roof and checking a timber column for a damp location.
Study "Composite structures" first (topic 59 of 112 in Civil & Structural). It covers the groundwork this topic builds on.
Anisotropic strength. Duration of load. Char depth in fire.
A timber floor joist 50×200 at 400 mm spacing spans about 4 m.
The next topic is "Masonry design", which builds directly on this one.
It is classed as Intermediate in Civil & Structural (topic 60 of 112). It is an intermediate topic. Work through the beginner topics in Civil & Structural first.
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