6.0 Design Approach

There are 2 methods of construction – typical and tie-down. Typical is the most common method of building whilst the tie-down method is required for cyclonic or high wind areas (as determined by an engineer). This guide provides information for both building methods.

Important Note

It is the responsibility of the architectural designer and engineering parties to ensure that the information in the Hebel PowerBlocks Design and Installation Guide is appropriate for the intended application. The recommendations of this guide are formulated along the lines of good building practice, but are not intended to be an exhaustive statement of all relevant data. Hebel accepts no responsibility for or in connection with the quality of the recommendations or their suitability for any purpose when installed.

Scope

The Hebel PowerBlocks Design and Installation Guide has been created to provide information for detached residential buildings. The design information in this guide has been condensed from the Hebel Technical Manual and AS3700 Masonry structures. The design basis is AS3700 Masonry structures, Section 12 Simplified design of masonry for small buildings. The footing and slab design is based on AS2870 Residential slabs and footings – Construction.

Refer to Table 6.1 for Building Geometry Limitations.

Design Parameters

The structural design information in this guide is based on the data and assumptions in Table 6.2, 6.3 and 6.4.

Design Sequence

Fig. 6.1 details Hebel recommendations for how to design a Hebel PowerBlock home.

Fig 6.1:  Flow Chart

Table 6.1: Building Geometry Limitations

 2 storeys max
 Max. height to underside of eaves  6.0m
 Max. height to top of roof ridge  8.5m
 Max. building width incl. verandah but not eaves  16.0m
 Max. building length  5x width
 Max. lower storey wall height  3.0m
 Max. upper storey wall height  2.7m
 Max. floor load width on external wall  3.0m (6.0m single span floor)
 Max. roof load width on external wall  3.0m (6.0m rafter/truss span)
 Max. floor load width on external wall  6.0m

Where the building geometry is outside the above limitations, the designer must refer to the Hebel Technical Manual and AS3700 Sections 1-11.

Table 6.2: Design Parameters

Hebel PowerBlock material properties:  
 Nominal Dry Density  470 kg/m2
 Working Density (S.T.)  611 kg/m2
 Working Density (L.T.)  500 kg/m2
 Characteristic Compressive Strength, f’m  2.25 MPa
 Characteristic Flexural Tensile Strength, f’mt  2.20 MPa
 Characteristic Shear Strength, f’ms  2.30 MPa
 Characteristic Modulus of Elasticity, EST 1125MPa
 Characteristic Modulus of Elasticity, ELT 562 MPa

Table 6.3 Design Parameters – Permanent and Imposed Actions

Permanent Actions (Dead Loads):
Floor – Superimposed 1.00 kPa
Roof – Tile 0.90 kPa
Roof – Sheet 0.40 kPa
Framed Floor/Deck – Timber 0.50 kPa
Framed Deck – Tile 0.50 kPa
Pergola Roof – Tile 0.80 kPa
Pergola Roof – Sheet 0.32 kPa
Hebel PowerFloor System 0.80 kPa
Hebel Floor Panel System – 250mm 1.90 kPa
Hebel PowerBlock Wall – 250mm, 2700mm (H) 4.60 kN/m
Hebel PowerBlock Wall – 150mm, 2700mm (H) 2.76 kN/m
Imposed Actions (Live Loads):
In accordance with AS 1170. 1:2002
Floor – general 1.50 kPa
Deck 2.00 kPa

Table 6.4  Design Parameters – Wind Actions (General wall areas)

Wind Classification
(AS4055)
Wind Pressure (kPa)
Serviceability, Ws Ultimate, Wu
N1 0.41 0.69
N2 0.41 0.96
N3 0.61 1.50
N4 0.91 2.23
N5 1.33 3.29
N6 1.82 4.44
C1 0.61 2.03
C2 0.91 3.01
C3 1.33 4.44
C4 1.82 5.99

Image 6.1:  Hebel PowerBlock home

Image 6.2:  Hebel PowerBlock home

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