Techniques to resist earthquake

Techniques to resist earthquake
Energy dissipation device
Bracing
Isolation
Bands
Shear walls

1. Presented by, Guided by, AKSHAY KUMAR V V Prof. SAJEEB R 7107 TECHNIQUES TO RESIST EARTHQUAKE 05-11-2016 1

2. Earthquakes constitute one of the worst natural hazards which often turn into disaster causing widespread destruction and loss to human life. The effects of earthquake vary upon the magnitude and intensity. Earthquakes occur every now and then all round the world, except in some places where earthquakes occur rarely. No structure on the planet can be constructed 100% earthquake proof, Only its resistance to earthquake can be increased. INTRODUCTION 05-11-2016 2

3. An Earthquake is the result of a sudden release of energy in the earth’s crust that creates seismic waves. Nepal earthquake(2015) ( Source:http :// www.eqclearinghouse.org /) WHAT IS AN EARTHQUAKE?? 05-11-2016 3

4. Bhuj earthquake(2001) ( Source:http :// bhujbolechhe.org ) 05-11-2016 4

5. Roll of Inertial Force, F=M*a Effect of Inertia in a building when shaken at its base. (Source: www.nicee.org/EQTips.php) EARTHQUAKE EFFECTS ON STRUCTURES 05-11-2016 5

6. Energy dissipation device Bracing Isolation Bands Shear walls TECHNIQUES TO RESIST EARTHQUAKE 05-11-2016 6

7. Its also called Dampers. Dampers act like hydraulic shock absorbers. Which absorb vibrations caused due to earthquakes. Usually for protecting tall buildings. Reduces the swaying of buildings. Installed along with Bracings 1.ENERGY DISSIPATION DEVICE 05-11-2016 7

8. Viscous Dampers Friction Dampers Yielding Dampers 05-11-2016 8 Commonly used Seismic Dampers

9. (Source: www.nicee.org/EQTips.php) Types of dampers 05-11-2016 9

10. Braced frames are prevalently utilized as lateral load resisting system. Bracing is usually seen with two digonal supports placed in an X shaped manner. Steel cables can be used for bracing. 05-11-2016 10 2.BRACING

11. Single Diagonals ( Source:www.slideshare.net ) Cross bracing ( Source:www.slideshare.net ) 05-11-2016 11

12. John Hancock Tower in chicago ( Source:www.nexus.globalquakemodel.org ) 05-11-2016 12

13. New kind of energy dissipating frame Energy absorbing fuse Provide excellent ductility and lateral stiffness. Timber pieces and mild steel are used 05-11-2016 13 2.1 Disposable Knee Bracing Frames

14. Knee bracings ( source:www.ideers.bris.ac.uk ) Knee bracings ( source:httpsembed.widencdn.net ) 05-11-2016 14

15. Base isolated structure is supported by a series of bearing pads which are placed between building and building foundation . Principle is easy and widely used. The main feature of the base isolation technology is that it introduces flexibility in the structures. Reduce the building acceleration by ¼ the acceleration of fixed base building Base Isolation Using tyre pads is an economical method. 05-11-2016 15 3. ISOLATION

16. 05-11-2016 16 Movement of Building with Base isolation vs No Base isolation Source:https :// nees.org /resources/3832) Concept of Rollers (Source:http.21stcenturybuilder.org/)

17. 05-11-2016 17 Seismic base isolation pads using scrap automobile tires ( Source:www.sefindia.org /forum/files/low)

18. Pasadena city hall ( Source:www.cityofpasadena.net ) 05-11-2016 18

19. CITY OF PAS CITY OF PASADENA(USA) ( Source:www.clarkconstruction.com ) 05-11-2016 19

20. Horizontal bands are the most important earthquake-resistant feature in masonry buildings They hold a masonry building as a single unit by tying all the walls together There are Four types of bands in a typical masonry building, Gable band, Roof band, Lintel band and Plinth band 05-11-2016 20 4. BAND

21. 05-11-2016 21 Horizontal Bands in masonry building (Source: www.nicee.org/EQTips.php)

22. (Source: www.nicee.org/EQTips.php) 05-11-2016 22

23. The 1993 Latur Earthquake(Central India)-one masonry house in Killari village had horizontal lintel band and sustained the shaking without damage (Source: Murty.C.V.R , 2015) 05-11-2016 23

24. Vertically oriented wide beams It carries seismic loads down to the bottom of foundation Provides large strength and stiffness to buildings Thickness generally varies from 150mm to 400mm in high rise buildings 05-11-2016 24 5. SHEAR WALL

25. Reinforced concrete shear walls in buildings Types of shear walls (Source: Murty.C.V.R , 2015) (Source: Murty.C.V.R , 2015) 05-11-2016 25

26. Two-storey building with multiple Two-storey building with multiple load paths in X direction load paths in Y direction ( Source:www.recoveryplatform.org ) 05-11-2016 26

27. Reinforcement details of RC walls ( Source:www.recoveryplatform.org ) 05-11-2016 27

28. The work in the field of earthquake resistant techniques is very important to have safe structures . Techniques for earthquake resistance is not strengthen the building, but to reduce the earthquake generated forces acing upon it. Effects made by the Earthquake mainly depends on acceleration of base and mass of building. 05-11-2016 28 CONCLUSION

29. Cancellara.D , Angelis.F.D (2016), Assessment and dynamic nonlinear analysis of different base isolation systems for a multi-storey RC building irregular in plan ,Computers and Structures, 79(Article in press). Fateh.A , Hejazi.F , Jaafar.M.S , Karim.I.A (2016) , Design of a variable stiffness bracing system : Mathematical modeling, Fabrication and dynamic analysis , Soil Dynamics and Earthquake Engineering, 80: 87-101 . Nobahar.E , Farahi.M , Mofid.M (2016),Quantification of seismic performance factors of the buildings consisting of disposable knee bracing frames , Journal of Constructional Steel Research, 124: 132-141. Murty.C.V.R (2015), Learning Earthquake Design and Construction , Earthquake tips, (www.nicee.org/EQTips.php). Yun-tian Wu, Dao Y.K,Yeong .B.Y (2016), Seismic performance of steel and concrete composite shear walls with embedded steel truss for use in high-rise buildings , Engineering Structures, 125: 39-53. www.nexus.globalquakemodel.org http://greenfieldgeography.wikispaces.com/Before+the+event https://nees.org/resources http://www.sefindia.org/forum/files/low_1_464.pdf www.recoveryplatform.org 05-11-2016 29 REFFERENCES

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