CONSTRUCTING ENVIRONMENTS LOG BOOK- WEEK 5- LEARNING LOOP COLUMNS, WALL SYSTEMS, TIMBER SHORT COLUMNS: are shorter (length) and thicker (crosssection). Axial loads • Short if the ratio of column length to the smallest cross section dimension is less than 12:1. For example: a 3000mm tall column with a 450mm x 300mm crosssection will have a ratio of 10:1. Thus short column.
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Become shorter when a compressive load is applied; fail when compressive strength is exceeded (either by applying too great a load or if the cross-section is too small). Fail by Buckle and Crush Compressive Strength (Pa) = Load (N) / area (mm2)
LONG COLUMNS: are taller (length) and slimmer (cross-section). Axial loads • Long if the ratio of column length to the smallest cross section is greater than 12:1. For example: a 6000mm tall column with a 450mm x 300mm cross-section will have a ratio of 20:1. Thus long column.
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Fail by BUCKLING.
WALLS: • Enclose • Separate • Protect interior from exterior • Moderate the climate • Filter light • Insulate from cold and heat • Major structural building system carrying load to ground STRUCTURAL FRAMES • Concrete • Steel • Timber (post and beams) Stud (Metal and Timber) LOAD BEARING WALLS • Concrete • Reinforced masonry • Solid Masonry • Cavity Masonry TIMBER PROPERTIES Hardness: Medium Fragility: Medium- Low Ductility: Low Flexibility: High Density: Heavy and light Conductivity: Poor Durability: Depends on type, seasoning Length: 0.3 m increments, max 6.0m