Earthquake resistant technique
- 1. Nishant Raj Kapoor Presentation on “Earthquake Resistant Techniques” 7/24/2019 1
- 2. OVERVIEW OF PRESENTATION Introduction Earthquake Resistant Methods Base Isolation Devices Energy Dissipation Devices/ Seismic Dampers Techniques Under Research IS Codes For Earthquake Resistant Designs In India References 7/24/2019 2
- 3. INTRODUCTION An earthquake is the shaking of the surface of the Earth, resulting from the sudden release of energy in the Earth's lithosphere that creates seismic waves. They are natural disasters of a generally unpredictable nature. 7/24/2019 3
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- 5. METHODS Basic approach is to reduce the earthquake generated forces acting upon the building; rather than strengthening it. Two main techniques: Base Isolation Energy Dissipation Devices 7/24/2019 5
- 6. BASE ISOLATION DEVICES Base Isolation Devices – separate building from building foundation by bearing pads. Lead Rubber Bearings Spherical Sliding Isolation Systems 7/24/2019 6
- 7. BASE ISOLATION DEVICES Supported by a series of bearing pads which are placed between the building and the building's foundation. In case of an earthquake: Fixedbase building deform and are damaged. Base isolated building rocks back and forth like a boat. Shaking is reduced by as much as 5 times 7/24/2019 7
- 8. ENERGY DISSIPATIONDEVICES (SEISMIC DAMPERS) Special devices introduced in building absorb the energy produced by seismic waves. •Viscous Dampers utilized the forced movement of fluids within the damper •Friction Dampers these utilize frictional forces to dissipate energy •Metallic Dampers utilize the deformation of metal elements within the damper 7/24/2019 8
- 9. TECHNIQUES UNDER RESEARCH 1. SHAPE MEMORYALLOYS Bounce back after experiencing large loads. Used in bearings, columns and beams and connecting elements. Most common alloys used are copper-zinc-aluminum- nickel, copper-aluminum-nickel or nickel-titanium. 7/24/2019 9
- 10. TECHNIQUES UNDER RESEARCH 2. MUSSEL FIBERS Elastomeric fibers combine stiffness and flexibility which helps mussel to attach to hard surfaces. Construction materials made of a similar blend of firm and flexible parts could help buildings withstand high-stress forces during an earthquake. Ratio of stiff-to flexible fibers = 80:20. 7/24/2019 10
- 11. TECHNIQUES UNDER RESEARCH 3. VISCO-ELASTIC DAMPERS CST30 Two layer of high damping rubber sandwiched between steel plates. Absorb energy produce from vibrations. 7/24/2019 11
- 12. 3. VISCO-ELASTIC DAMPERS CST30 Advantages over traditional damping system. Effective utilization of interior space. Improvement in the degree of freedom of design. Accepts different vibration types. High performance and high quality. Environmental friendliness. Maintenance free. 7/24/2019 12
- 13. WORK ON EARTHQUAKE RESISTANCE IN INDIA In India, base isolation technique was first demonstrated after 1993 Killari earthquake. Two single storey buildings were built with rubber base isolators resting on hard ground. The four storey bhuj hospital building was built with base isolation technique after 2001 bhuj earthquake. 7/24/2019 13
- 14. IS CODES FOR EARTHQUAKE RESISTANT DESIGN IS 1893 (Part 1), 2002, Indian Standard Criteria For Earthquake Resistant Design of Structures (5th revision). IS 4326, 1993, Indian Standard Code of Practice for Earthquake Resistant Design and Construction of Buildings (2nd revision). IS 13827, 1993, Indian Standard Guidelines for Improving Earthquake Resistant of Earthen Buildings. IS 13828, 1993, Indian Standard Guidelines for Improving Earthquake Resistant of Low Strength Masonry Buildings. IS 13920, 1993, Indian Standard Code of Practice for Ductile Detailing of Reinforced Concrete Structures Subjected to Seismic Forces. 7/24/2019 14
- 15. REFERENCES www.google.com www.wikipedia.com www.researchgate.net 7/24/2019 15 Special thanks to all the people who made and released related awesome resources for free.
Editor's Notes
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