Thursday, April 12, 2012

Did you feel the tremor?

This was the question I heard from everyone I met during our morning walk at Mantri Synergy. Probably, some didn't believe when I told  I slept through the Wednesday afternoon tremor. And, this isn't a put on, I first heard of it on TV.  And then, a couple of our Mantri neighbours, who were away in the city, phone us to check out if things were okay at our end.
 OMR's proximity to the coast prompted a relation of ours to suggest we  moved to their apartment at Velachery, in view of  tsunami warning. We can see Muthukadu Lake, and the sea beyond, from our 9th floor flat at Mantri's. Even  two hours after they sounded the tsunami warning the sea appeared calm and tideless
If anyone seemed agitated and breathless with anxiety, it was some TV-wallahs reporting live from  Chennai. But the papers this morning said, This time around, no wave of panic..., as if  The Hindu headline writer felt let down by tsumani's failure to show up.  As for  tremor, seismic centre subsequently admitted that intensity of the quake wasn't as high as was feared initially,  and it wasn't the type of  quake  that sent out  tsunami waves.
This morning I watched on Puthiya Thalaimurai channel  a talk-show at which  they discussed Chennai's  quake-readiness, as evident from the  response of people and administration  to Wednesday's quake and tsunami warning. A more pertinent issue for those of us living in high-rise buildings  is whether Mantri and other developers have taken into account the seismic factor and wind velocity on OMR in their design and construction.  
Mantri resident Gurusamy Pandiyan (A-603) may recall  raising the issue one year back in Common Floor  discussion forum. Chennai is in Seismic Zone III (Upto 6.9 Moderate risk). And Mantri's say Synergy is 'Seismic Zone III compliant structure'. Has anyone  checked this out with developers ?
Mr Pandiyan's query and an article on wind-engineering in The Hindu prompted me to e-mail someone I knew  should know about such matters.
My mail, dated March 26, 2011: Today's Hindu (Bangalore edition)  carries in Property Plus section an article by K Suresh Kumar on the importance of  wind engineering in high-rise buildings. The wind power, it says, could sway  tall buildings. It may not be perceptible, but it can be felt by residents. I trust Mantri architects factored in the wind-load factor, height/.width ratio, considering Mantri Synergy is their first close-to-sea project, which is likely to have relatively higher wind current.
Wind flow:  Our structural consultants, Chetna from Bangalore, have pointed out that since wind velocity is higher in Chennai, as compared to Bangalore and Hyderabad, the steel consumption for our structure will be relatively higher...we have ensured that our structure will stand wind of the known velocity.
Quakes resistance: We have taken into account the seismic zone requirements; and the structure can withstand earthquakes of Seismic Zone II levels, which is only a zone higher than that of Japan.


  1. GVK Uncle , so we are safe ...:).Indeed Hats off to you for all valuable information.

    1. Safe ? So would Mantri's have us believe. No point in not believing them. And believing in this case is good for our well-being.

  2. I have recently moved to Mantri Synergy with my family as a tenant.I don't want to discuss here about the common issues faced by most of the residents or about the recent issue about refusing the club facilities to the tenants since steps are being taken to solve the issues which of course will take some time.

    Here I want to write my experience on the day on which the strong earth quake of magnitude of 8.6 Richter scale in Sumatra and the resultant mild tremor felt in Chennai on Wednesday.

    My wife and myself were watching a TV programme and both of us felt a little shaking of the sofa. We thought that it was due to a tremor and went out our flat and noticed that our neighbours with their children also came out telling that they also felt the tremor and advised that it is better go down the steps rather than going by the lift.

    Meanwhile my son also called from his office and told us to get down to the basement and move away to a safe distance. So we went down to the basement from the eighth floor and stood away from the building. Apart from us and our neighbours we could not see anyone.

    After some minutes about 5 persons came down from different blocks and they informed that got the news about the tremor through their relatives/friends and TV news. We could see many persons standing outside their flats in different floors of different blocks without the knowledge of the tremors and with out understanding the danger to their life if the earthquake is strong enough to affect the building.

    I could not understand why there was no alarms raised/public announcement made advising all the residents to evacuate the building immediately.Such a system must be there as followed in many high raised residential buildings/offices

    I also don't know whether any mock drills are conducted to create awareness among the residents about the steps to be taken at the time of disasters like fire,earth quake etc. If not it is better to conduct such mock drills at the earliest utilising the services of government agencies like Fire Department etc.

    (Retired Assistant General Manager,India Bank)

    Resident of F 802

    (Also visit my blogs on 'Knowledge Sharing 'at (English)

    and 'என் இனிய தமிழ் உலகம்' at (Tamil))

  3. I have noted the following errors in my above article and give below the corrections:

    Wherever I have mentioned basement, please read it as Ground floor open space.

    Indian Bank wrongly spelt as India Bank.