Studio Journal Week 5 Queens College Extension This week we looked at the building plans of the college in more detail. In particular the primary and secondary structures of the building as well as the environmental capabilities of the materials used. Description and Classification of Structural systems Foundations and Footings The extension of the college rests of a 150mm reinforced concrete floor slab. In comparison to the extension, the rest of the building lies on existing footings. Other structural systems in place are the excavated concrete binding piers underneath the slab. Deep pad footings are also located around the structure. There are also edge beams and internal beams listed on these plans, which also provide stability for the slab structure. These beams are located within the slabs. The edge beam is located on the outer side of the slab while the internal beams are found within the middle pier of the slab Primary Structure The primary structure of the building is the buildings framework. All the necessary structural beams and columns used to keep the building standing make up the primary structure. There are two parts to the primary structure, the horizontal and vertical elements. The horizontal element in this renovation is the single story roof. This is made up of rood beams (RB), ceiling joists (CJ) and Canopy Beams (CB). Rafters are also part of the primary structure as they support the load of the roof. These essential beams and supports are connected to wall plates and columns supporting the structure. The vertical structure consists of columns supporting the roof of the Queens college extension. Wall plates make up the rest of the walls for the extension.
Secondary Structure The secondary structure is the cladding and exterior fittings around the primary structure. This structure does not support the main loads of the building. The main
vertical secondary structure of the extension is the precast concrete panels that are attached to the wall plates. These are 150 min panels of concrete. Windows and doorframes are also included in the secondary structure of the building. Other parts of the secondary structure include the bluestone steps and the vinyl covering in the bar and laundry areas. Along with this there is extensive lighting and electrical wiring running throughout the primary structure.
Identification and description of structural materials Materials include: Timber: As lining board and Flooring in the hall, entry and bistro areas. Bricks: As flooring in the entrance Tiles: Flooring in the Central Tower and Gym Rubber: Flooring in the Turn room Concrete: Walls in the southern part of the extension, Flooring as aggregate concrete and footings ad stumps. Steel: Window capping and handrails Vinyl: Floor in the Emporium and Bar, Band room and the stage. Perforated Rheinzink: Roof structure around the courtyard.
4 Identify structural joints This is a typical footing or a wall connection. It has a nonbearing concrete binding to replace poor soil. This image shows the placement of precast panel, the steel rondo stud and the plasterboard.
The detail below is of a sliding doorjamb. It shows the placement of both internal and external doors as well as the exact location of the channel and flexible waterproof sealant.
This is a close up of the block window joinery to be used in the fitting of the block windows. This shows the concrete wall panels with the expansion material to be used, mortar thickness as well as structural elements like the steel rod bracing.
5 – Identify and explain the use of different structural fixings Concrete – in this project concrete has been used in many different ways, For example, concrete has been used to improve the reactivity of the soil, no steel is used in this concrete it merely acts as a extra footing for the building to ensure the ground is able to withstand the load of the building. Bolts – You can see in the drawings that it is specified that pre-cast concrete wall panels will be bolted together Weld- During a site visit you can see that the steel had been welded in certain parts Screws – On the inside of the concrete wall panels there is a timber framing, screws and nails are used for the timber to be held together 6 – Sustainability and Environmental Analysis Carbon Footprint - Concrete is a key element in this construction, it is used for both the footing systems as well as the pre-cast walls and exposed aggregate concrete flooring. The concrete manufacturing business accounts from almost 5% or the world’s man made C02 emission so concrete does have a relatively high carbon footprint. (The Cement Sustainability Initiative: Progress report, World Business Council for Sustainable Development, published 1 June 2002)
Embodied Energy It is commonly said that a large building complex â€˜s energy consumption usually takes about 4-5 years to surpass the energy used in its constructing, it is not just the electricity used to power tools or fuel to power machines but also the energy used to produce materials. Concrete retains extremely large amounts of embodied energy the processes used for the extraction of concrete are very energy intensive. This also goes for the pouring and holding of concrete. Steel is another mineral that is mined. Steel requires refining and moulding for it to be made into a usable form. Energy is used in its extraction from the ground, its refinement from an ore and its development into a useable product. Timber grows by itself although plantations have extensive maintenance costs associated with the size of such developments. There is embodied energy in the transportation and milling of timber to get it to constructing sites and into a usable material. However this material has the lowest embodied costs out of the three mainly due to its ease of access. Recyclability Many materials in these buildings can be recycled, most of the building can be recycled however in many cases it has proved more economically efficient to simply dump in land fill. Concrete can be recycled, it can be broken up again and mixed with cement and reused as well as the steel reinforcement which is funning through the concrete Steel can be melted down and re-moulded. Glass can also be recycled, although it is typically wasted due to the high costs associated with recycling.