Presentation on theme: "YAN WENLI A9SJ2002 2010/05/07 Building structure & Earthquake resistant capacity."— Presentation transcript:
YAN WENLI A9SJ /05/07 Building structure & Earthquake resistant capacity
Outline Building structure types Adobe Masonry Reinforced Concrete Steel Timber Earthquake resistant capacity showed in earthquake cases 1995/01/17 Hyogo-ken earthquake, Japan 1999/08/17 Kocaeli earthquake, Turkey 2003/12/26 Bam earthquake, Iran 2008/05/12 Wenchuan earthquake, China
Building structure I Adobe Raw material Sand Clay Manure Water Fibrous or organic material (sticks and/or straw) Shaped into bricks using frames and dried in the sun
Building structure I Advantage: Durable(account for some of the oldest extant buildings on the planet) Great thermal mass(for living comfort) Disadvantage: Susceptible to seismic damage Great weight of adobe bricks
Building structure II Masonry Raw material Brick Stone(marble, granite, travertine, limestone) Concrete Block Glass block tile
Building structure II Advantage: Great thermal mass Heat resistance Resistance to projectiles Disadvantage: degradation of wall surfaces due to extreme weather Heavy and easy to crack
Building structure III Steel Constituent Iron(mostly) Carbon(between 0.2% and 2.1% by weight) Other alloying elements(such as manganese, chromium, vanadium, and tungsten) Varying the amount of alloying elements and form of their presence in the steel controls qualities such as the hardness, ductility, and tensile strength of the resulting steel.
Building structure III Advantage: High strength Light weight Great ductility and toughness Disadvantage: Expensive Vulnerable to fire
Building structure IV Reinforced Concrete concrete in which reinforcement bars ("rebars"), reinforcement grids, plates or fibers have been incorporated to strengthen the concrete in tension.
Building structure IV Advantage: Enlarged tensile strength Durable Resistance of fire Disadvantage: Expensive Technical difficulty
Building structure V Timber Timber framings refer to structures utilizing heavy timbers jointed via pegged mortise and tenon joints.
Building structure V Advantage: allowing great rapidity in erection on site and more precise alignments. (an "average"-sized timber- frame home can be erected within 2–3 days) Light weight Great Elastic property Disadvantage: Poor prevention of capillary movement of water Burn easily
Earthquake archive I 1995/01/17 Hyogo-ken earthquake, Japan RC structure – not collapse easily
Earthquake archive I Fire-vulnerable timber structure should be paid great attention, as fire usually take place together with and earthquake.
Earthquake archive II 1999/08/17 Kocaeli earthquake, Turkey
Earthquake archive III 2003/12/26 Bam earthquake, Iran Masonry structure
Earthquake archive IV 2008/05/12 Wenchuan earthquake, China Expose “tofu-dregs projects” (jerry-built projects, low- quality construction, Chinese: 豆腐渣工程 ) Building structure of reinforced concrete should have good earthquake resistant capacity. However, in the case that the steel bar is not thick enough, expected strength can not be supported.
Conclusion In respect of earthquake resistant capacity, building structures of steel and timber are the best. However, reinforced concrete is an eclectic choice when taking into consideration the economic factor. To be mentioned, it’s important to produce and exploit high-quality RC rather than tofu-dreg material.