10-06-2017, 07:04 AM
EARTHQUAKE AND THEIR EFFECTS ON STRUCTURES
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Definition
Earthquake is defined as movement of surface of earth due to adjustment between layers of earth and due to sudden release of energy in the earths crust that creates seismic waves.
SEISMIC DESIGN PHILOSOPHY FOR BUILDINGS
Earth quake - resistant buildings.
Earth quake design philosophy
Damage in buildings : unavoidable
Acceptable damage ductility
HOW DO COLUMNS IN RC BUILDINGS RESIST EARTH QUAKES
Steel reinforcement in columns
Closed ties at close spacing improves performance of column under strong EQ shaking.
Closed ties with 135 degree hooks are required as per Indian Ductile Detailing Code IS:13920-1993
180 degree links are necessary to prevent the 135 degree tie from bulging outwards.
Lap length should be provided only in the middle half of the column.