[WEEK 5] 1 Engineered & Timber Products
GLULAM –Glued laminated timber. Makes timber have more depth, good for structural beams
CLT – Cross Laminated Timber. Alternates direction by 90degrees each sheet.
Sources (left to right): http://www.ewpa.com/images/def_glulam.jpg http://jasonw11030714northumbria.files.wordpress.com/2014/02/cross-‐lam.jpg
MDF – Medium Density Fiberboard
Plywood – A number of sheets stuck together to create a stronger product
Chipboard/Strand board – Same as plywood but with wood chips
Sources (left to right): http://www.paxtonwood.com/Portals/0/images/sheetstock/mdf.jpg http://www.forestproductssupply.com/images/lumber/Plywood1.jpg http://www.nextdaydiy.com/images/products/medium/1294932834-‐32903800.jpg
[I-‐Beams, Box beams and Timber flanged steel web joints (COMPOSITE) sketch.]
Gehry’s Own Home -‐ Stud frame: light weight timber construction -‐ Uses ‘raw’ engineered products, no facades -‐ Often using construction materials for decorative purposes. Source: http://4.bp.blogspot.com/-‐ UFj6uV4H_Oo/TcatSmTRY0I/AAAAAAAAAFs/PADM8Ph1Zhk/s1600/lg_frank-‐gehry-‐house-‐ santa-‐monica2.jpg
[Materials Sketch] Material properties table Property Timber Hardness Medium-‐Low. Can be marked Fragility Medium-‐Low. Generally will not shatter or break Ductility Low. In Green state can be manipulated in to different shapes Flexibility/ High Flexibility & Plasticity Medium Plasticity Porosity/ High, varies on season, Permeability finishing and fixing. Density Varied Conductivity Poor Conductor of heat and electricity Durability Can be durable if made well
Concrete
Steel
[WEEK 5] 3 Reusable/ Recyclability Sustainability / Carbon Footprint Cost
Very High. Second hand timber is desirable. Very low embodied energy. Renewable if sourced correctly (plantations) Generally Cost Effective.
Timber Properties and Considerations [knot types sketch] -‐ Strength grade: F-‐Grade & MGP grading used to identify particular timber elements. -‐ >15% Moisture content = unseasoned. -‐ < 15% Moisture content = seasoned (dried in a kiln) -‐ Weakness points: Knots (different types) Arris, Centre and edge, also weak with the slope of grain. Know always goes to the top as it compresses the knot rather than stretching it -‐ Strong parallel to grain, weak perpendicular to grain From Wood to Timber [Ring type & Saw type sketch/photo] -‐ Dark ring = Late wood -‐ Light ring = Early wood -‐ Softwood/hardwood slide -‐ Quarter Sawn / back Sawn / radial sawing Walls, Grids & Columns Wall Systems: -‐ Structural frames: timber, concrete or timber -‐ Load bearing walls: concrete or masonry (reinforced) à [sketch blocks with steel rod inside, compare with photo] -‐ Studwalls: Light guage steel, timber -‐ Cavity typically about 50mm in walls -‐ Nogging beam put half way along the timber column (vertical stud)
-‐ Cross bracing and ply bracing Key Terms Stud: Vertical member in a stud framing system. Nogging: Horizontal member in a stud framing system Lintel: Vertical member (beam) that hangs over the doorway, taking and dispersing all vertical forces equally through each column of the dorrway. Axial Load: A force that passes through the centroid of the object perpendicular to the plane. Buckling: The bending or distorting of a member when in compression, usual failings of a long column. Seasoned Timber: Timber that has been dried in a kiln resulting in it having less than 15% moisture content.