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CTD 2 –Exercise 2 : Analysis of Steel Framed Structure – House Sue Primary Structure The primary structure acts as the main framework of a building. The primary structure transmits the loads exerted on the building. These forces can be Wind forces Dead loads – the actual weight of the structure itself Live loads – the load exerted by people and other weights in the structure. For House Sue, the primary structure is composed of the portal frame which is made up of stanchions (columns) and rafters which are prefabricated and then bolted on site. This having provided faster and easier erection of the structure.

Secondary Structure The secondary structure is fixed to the primary structure. The secondary structure is mainly incorporated to support the primary structure and add stability by bracing and preventing the primary structure from failing due to forces exerted upon it. The secondary structure is composed of the diagonal braces, steel purlins as well as the wall which was used for vertical wall bracing.

Tertiary Structure The tertiary structure is the cladding elements of the structure. These serve to enclose the structure and do not provide any structural support. The tertiary structure also serves as an aesthetic element for the structure. The tertiary structure is composed of timber slats to prevent glare, the corrugated roofing material, the cladding glass windows and doors which enclose the structure.

Alfred Vinyu

210044535

Construction and Detailing 2: House Sue Analysis


Primary

Structure

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Portal frame. Made up of stanchions and steel rafters. Secondary Structure – Bracing. Vertical roof braces and cross bracing which supports the primary structure and adds stability..

Tertiary Structure – Roof sheeting, glass windows, doors. Enclosing elements..

1:100 draught of House Sue

Alfred Vinyu

210044535

Construction and Detailing 2: House Sue Analysis


CTD 2 –Exercise 2 : Analysis of Steel Framed Structure – House Sue Primary Structure 6 portal frames made of stanchions (columns) and trusses make up the primary structure of the building.

The portal frame is one structural element. The columns are made up of Hsection beams. These take a higher load and are used to support the rafters.

The strength of the Columns prevents failure and buckling at these points due to gravitational and imposed loads acting vertically downwards on them.

The webb holds the top and bottom flanges and prevents them from buckling.

Secondary Structure

The bracing keeps the structure stable in longitudinal section.

Alfred Vinyu

210044535

Without bracing, should there be any longitudinal wind forces, the structure would fail in stability.

Construction and Detailing 2: House Sue Analysis


And to prevent this, a horizontal beam is used to hold them in position in tension.

Due to loads imposed on the trusses, the columns may be pushed out due to horizontal forces acting on them

The wall is used as a bracing element. It is also used as vertical roof bracing to support the roof structure. Although it does not hold up the structure, it is used in bringing stability to the structure

The purlins are bolted to the rafters and hooked to the roof sheeting with a smooth ceiling finish in between.

Without bracing, should there be any longitudinal wind forces, the structure would fail in stability.

Tertiary Structure The corrugated roof sheeting, glass windows and cladding, and doors make up the tertiary structure as they play no role in supporting the structure but function to enclose it.

Rodseth, M. Principles of Structure in Buildings. Available http://dl.dropbox.com/u/29112329/CTD%202%20 NOTES principles%20of%20structure%20in%20buildings.pdf (2011/06/04) Available http://www.colorcoat-online.com/en/technical/functional_design/buliding_structure/ (2011/06/27) Available http://www.aspenpitkin.com/Portals/0/docs/City/Comdev/HPC/chapter_8.pdf (2011/06/27)

Alfred Vinyu

210044535

Construction and Detailing 2: House Sue Analysis


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