Mechanical Properties

Mechanical properties have been determined in limit state format form with a comprehensive testing and evaluation program carried out by Hyne Timber. The modulus of rigidity is calculated by using G = E/15.

Density is a measured property and is determined as average seasoned density. However properties such as Bearing Strength Perpendicular to Grain, Bearing Strength Parallel to Grain, Shear Strength at Joints Details and Tension Strength Perpendicular to Grain are secondary properties which are depending on the strength group for the material and are determined in accordance with AS1720.1-2010. Further joint group are based on the material used and the groups are defined based on species and density as per AS1720.1-2010.

 

PropertyBeam 21
Stress GradeGL21
Bending StrengthFb = 50MPa
Tension StrengthFt = 25MPa (parallel)
Ftp = 0.8MPa (perpendicular)
Shear StrengthFs = 5.0MPa (in beam)
Fsj = 8.4MPa (at joint details)
Compression StrengthFc = 50MPa
Bearing StrengthFl = 67MPa (parallel)
Fp = 23MPa (perpendicular)
Modulus of ElasticityE = 21,000MPa
Modulus of RigidityG = 1,400MPa
Strength GroupSD2
Joint GroupJD2
Density1000kg / m3

 

Download the Characteristic Properties of all Hyne Timber glue laminated products here:

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Capacity Factor

Values of capacity factor (F) for calculating the design capacity of (F Rd) of structural members. Note that in this context, 'area' should be taken as the plan area.

Structural member in houses for which failure would be UNLIKELY to affect an area greater than 25m2; or SECONDARY member in structures other than houses:

F = 0.95

Structural member in houses for which failure would be LIKELY to affect an area greater than 25m2; or PRIMARY structural member in structures other than houses:

F = 0.85

Primary structural member in structures intended to fulfill an essential service or post disaster function:

F = 0.75

Conductivity K

Where moisture content is below 25%, approximate thermal conductivity k across the grain can be calculated with a linear equation of the form:

  • k = Gx (B + Cx) + A

Where Gx is specific gravity based on oven dry mass and volume at moisture content x (%) and A, B, and C are constants.

For Gx > 0.3, temperatures around 24ºC and x < 25% MC, the values of the constants are as follows:

  • A = 0.01864
  • B = 0.1941
  • C = 0.004064 (k in W m-1 K-1)

Gx = 0.65

Camber

Hyne Timber glue laminated (glulam) beams with a “C” postfix designates a vertical camber radius of 600m. An “S” postfix designates a straight beam profile.

Alignment tolerance of both straight and cambered beams shall be no more than 1mm per metre of beam length. Cambered beams are generally supplied with a marking stamped on the top edge of the beam. Unless specifically requested (such as for large cantilevers), cambered beams should not be installed with the camber arch facing downwards.

Download the Beam 21 Camber overview here:

 

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Service Classes

SERVICE CLASS 1

Characterized by a moisture content in the materials corresponding to a temperature of 20ºC and relative humidity of the surrounding air only exceeding 65% for a few weeks per year (Note: The average equilibrium moisture content in most glue laminated timber products will not exceed 12%).

SERVICE CLASS 2

Characterized by a moisture content in the materials corresponding to a temperature of 20ºC and relative humidity of the surrounding air only exceeding 85% for a few weeks per year (Note: The average equilibrium moisture content in most glue laminated timber products will not exceed 20%).

SERVICE CLASS 3

Characterized by climatic conditions leading to higher moisture contents than Service Class 2, or where timber is directly exposed to sun and/or rain (Note: Refer to Hyne Timber Technical Data Sheets for further information).

Technical Data Sheets
Refer to Hyne Timber Technical Data Sheets (TDS) 5, 6, 8 and 9 for storage, installation and maintenance advice.
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