Earthquack engineering
- 2. EARTHQUAKE ENGINEERING • DESTRUCTION DUE TO EARTHQUAKE • EARTHQUAKE WAVES • EARTHQUAKE RESISTING BUILDINGS • CONCLUSION
- 3. DESTRUCTION DUE TO EARTHQUAKE • ALL BUILDINGS CAN CARRY THEIR OWN WEIGHT. • THEY CAN USUALLY CARRY A BIT OF SNOW AND A FEW OTHER FLOOR LOADS AND SUSPENDED LOADS AS WELL, VERTICALLY; SO EVEN BADLY BUILT BUILDINGS AND STRUCTURES CAN RESIST SOME UP-AND-DOWN LOADS. • BUT BUILDINGS AND STRUCTURES ARE NOT NECESSARILY RESISTANT TO SIDE-TO-SIDE LOADS • THEY ARE OFTEN THE FIRST TO FAIL. IT ONLY TAKES ONE TO FAIL FOR THE WORST SORT OF DISASTER, THE PANCAKE COLLAPSE SO FAMILIAR TO ANY ONE WHO HAS SEEN THE RESULTS IN ARMENIA, MEXICO, TURKEY, IRAN, PERU, AND NOW PAKISTAN AND KASHMIR.
- 4. EARTHQUAKES DO NOT KILL PEOPLE IMPROPERLY DESIGNED STRUCTURES DO…. Kobe incident Haiti destruction
- 5. EARTHQUAKE WAVES • AN EARTHQUAKE MOVES THE GROUND. IT CAN BE ONE SUDDEN MOVEMENT, BUT MORE OFTEN IT IS A SERIES OF SHOCK WAVES AT SHORT INTERVALS, LIKE OUR RIPPLES FROM THE PEBBLE IN THE POND ANALOGY ABOVE. IT CAN MOVE THE LAND UP AND DOWN, AND IT CAN MOVE IT FROM SIDE TO SIDE • ALL BUILDINGS CAN CARRY THEIR OWN WEIGHT (OR THEY WOULD FALL DOWN ANYWAY BY THEMSELVES). THEY CAN USUALLY CARRY A BIT OF SNOW AND A FEW OTHER FLOOR LOADS AND SUSPENDED LOADS AS WELL, VERTICALLY; SO EVEN BADLY BUILT BUILDINGS AND STRUCTURES CAN RESIST SOME UP-AND- DOWN LOADS.
- 6. If the sideways resistance comes from diagonal bracing then it must also go equally all round in both directions. Where possible, it should be strong enough to accept load in tension as well as compression: the bolted or welded connections should resist more tension than the ultimate tension value of the brace (or well more than the design load) and it should not buckle with loads well above the design load. And the loads EARTHQUAKE WAVES
- 7. • . IF THE SIDEWAYS LOAD IS TO BE RESISTED WITH MOMENT RESISTING FRAMING THEN GREAT CARE HAS TO BE TAKEN TO ENSURE THAT THE JOINTS ARE STRONGER THAN THE BEAMS, AND THAT THE BEAMS WILL FAIL BEFORE THE COLUMNS, AND THAT THE COLUMNS CANNOT FAIL BY SPALLING IF IN CONCRETE. AGAIN THE RIGID FRAMING
- 8. EARTHQUAKE RESISTING BUILDING • BASE ISOLATION METHOD • ENERGY DISSIPATION DEVICE ->(SEISMIC DAMPERS) • KEEPING BUILDING UP THRUST
- 9. BASE ISOLATION • BUILDING IS RESTED ON FLEXIBLE PADS(BASE ISOLATERS) • WHEN EARTHQUAKE STRIKES BUILDING DOES NOT MOVES • IT IS SUITABLE FOR HARD SOIL ONLY
- 10. Spherical-sliding isolation Lead rubber bearing Types of isolations
- 11. ENERGY DISSIPATION DEVICE SEISMIC DAMPERS • THESE ARE USED IN PLACE OF STRUCTURAL ELEMENTS SUCH AS DIAGONAL BRACES • ACTS LIKE THE HYDRAULIC SHOCK ABSORBERS IN CARS • WHEN SEISMIC ENERGY IS TRANSMITTED THROUGH THEM,DAMPERS ABSORB PART OF IT
- 12. TYPES OF SEISMIC DAMPERS • VISCOUS DAMPERS • FRICTION DAMPERS • YIELDING DAMPERS • VISCOELASTIC DAMPERS
- 13. KEEPING BUILDING UP RIGHT • RECENTLY JAPAN DISCOVERED THIS TECHNIQUE • THE MAIN CONCEPT BEHIND THIS METHOD IS ,WHEN EARTHQUAKE STRIKES THE SYSTEM DISSIPATES ENERGY IN THE BUILDING CORES AND EXTERIORS • THE FRAMES ARE FREE TO ROK UP AND DOWN WITHIN FITTINGS FIXED AT THEIR BASES
- 14. CONCLUSION •BY THE ABOVE METHODS WE CAN PROTECT OUR BUILDINGS FROM EARTHQUAKES AND PROTECT MANY MORE LIVES AND REDUCE THE LOSS OF PUBLIC PROPERTY AND NATURAL RESOURCES
- 15. ANY QUERIES……..
- 16. THANK YOU