Annexure VII- Protection against Hazards

  1. Protection of areas from earthquakes
  • In those areas where there are no dangers of soil liquefaction or settlements or landslides, all building structures and infrastructures should be designed using the relevant Indian Standards as provided in the Building Regulations and the National Building Code.
  • Soils prone to liquefaction due to earthquakes can be improved to prevent the possibility of liquefaction.
  • Buildings and structures could be found on deep bearing piles going to non-liquefiable dense layers.
  • Steep slopes can be made more stable by terracing and construction of retaining walls and breast walls, and by ensuring good drainage of water so that the saturation of the hill-slope is avoided.
  • Any other appropriate engineering intervention to save the building structures or infrastructure from earthquakes.

1.1. For structural design the Seismic Microzonation Thematic Maps prepared by India Metrological Department shall be referred. Details of Maps are as under-

  1. MAP-1: Average Sheer velocity at 30 m depth(m/s)
  2. MAP-2: Peak Frequency Map based on H/V ratio
  3. MAP-3: Peak Ground acceleration (PGA) at surface for MCE
  4. MAP-4: Peak Ground Acceleration (PGA) at surface for DBE
  5. MAP-5: Spectral Acceleration at 0.1 Second for DBE
  6. MAP-6: Spectral Acceleration at 0.3 second DBE
  7. MAP-7: Spectral Acceleration at 0.5 second DBE
  8. MAP-8: Spectral Acceleration at 1.0 second DBE
  9. MAP-9: Spectral Acceleration at 0.1 second for MCE
  10. MAP-10: Spectral Acceleration at 0.3 second for MCE
  11. MAP-11: Spectral Acceleration at 0.5 second for MCE
  12. MAP-12: Spectral Acceleration at 1.0 second for MCE
  13. MAP-13: Liquefaction at 0.9 mbgl
  14. MAP-14: Hazard index

2. Protection from cyclonic wind damage

Buildings, structures and infrastructures in the cyclone prone areas should be designed according to the Indian Standards and Guidelines as provided in the Regulations and the National Building Code.

Note: Similar protection methods could be used against flooding caused in cyclone prone areas by high intensity rains or by the storm surge through zoning.