www.sefindia.org

[amitjha]

Mumbai billboard collapse #GhatkoparHoardingCollapse
Prayers for injured and rescued. Rest in peace 14 unfortunate citizens. Accountability must be fixed and justice must prevail. https://t.co/dilFvG2DRW https://t.co/62pHfeQX0f pic.twitter.com/Cs8QeInEzB
— Structural Engineers (@sefindia) May 14, 2024

https://twitter.com/i/status/1790359586039353591

Read more

https://www.news18.com/india/mumbai-hoarding-collapse-did-bmcs-may-2-letter-to-railways-foretell-tragedy-blame-game-continues-8891242.html

[amitjha]

Mumbai hoarding collapse claiming 16 lives and dozens injured.
Key questions

    

1. if this was illegal hoarding, who is responsible?    
   
2. Technically, are there any design guidelines being followed to ensure hoardings sustain storm wind loads without collapsing ?    
   
3. Nationwide, Most metros have massive hoardings. They are the time bomb ticking in the absence of compliance.     
   
4. We have many engineers in the forum, they can tell  general trend if hoardings around us are engineered structures or just fabricated by contractors bypassing engineers to design the same. Hoardings beyond a certain size must go through a rigorous analysis and design process. Advertising agencies must be audited and every hoarding must display the name of the engineer who designed it and the permission from authorities for installation. All non engineerds hoardings must be taken down before another tragedy strike us.

The blame game will continue, lets discuss solutions to the problem.

Read more about this tragedy in news items

https://www.news18.com/india/mumbai-hoarding-collapse-did-bmcs-may-2-letter-to-railways-foretell-tragedy-blame-game-continues-8891242.html

Video of collapse

https://twitter.com/i/status/1790359586039353591

best regards

Amit Jha

[vikram.jeet]

Hoarding  - Support structure design
  
Hoardings support structure is in steel with light weight billboards BUT  under wind conditions  heavy moments develop due to wind horizontal forces as we all know.


I think following points to be kept in view :-
1) Structure to be designed under :-
a) Wind perpendicular to hoarding board
b) Wind at 45 degrees ,, I. e DIAGONAL WIND hitting the board
45 degree wind case is essential in case steel columns have Iyy < Ixx,, Base plate is rectangular (not square) and steel columns Footing is rectangular (not square)

case A) Hoarding structure from ground
1) Foundation size and  Foundation depth below existing surface level shall be adequate,, so that sufficient soil weight available for stability against overturning . with permitted FOS.


2) Base Plate to be designed for wind moments and Anchor bolts to be designed  for Tension forces  arising from wind moments

3) Hoarding columns need to be braced with x bracing,, this help in diagonal winds hitting board for component of wind force in that dir. Other component will be perpendicular to board.

Case B) Hoardings from building roof tops
Supporting columns must be anchored  fm rcc columns  . .Otherwise  steel columns must have Back soping members embeded in additional   Brick pillars  at back providing counterweight  plus front columns supporting hoarding anchored fully in wall to be ensured.
BRACING between columns as well as back sloping members to be provided.

[alpa_sheth]

Hi All,

I was waiting for more animated discussions on this topic. Most of us perhaps know that Ghatkopar is one of the busiest and wealthy suburbs of Mumbai and is closer to South Mumbai. I don't get to go to that side of Mumbai much, but I am more of the exception. A majority of Mumbaikars must have been seeing this hoarding and wowing at its sheer size. Hundreds of Municipal Engineers, Deputy Municipal Commissioners (most are civil engineers) would have seen the hoarding multiple times.  120'x120' ie 14400 sq ft or roughly 1500 sq m. This would mean about 15 apartments of 1000 sq ft could have accommodated in the size of that hoarding! Did nobody wonder, by the looks and size of it and its five supporting columns if the structure was safe?

Everytime there is a failure of this type, the Municipal Authorities will go into the "save my backside" mode and say that it was illegal. Why do we conflate (mix up) safety and illegality? Are the Municipal Authorities saying that if they had given permission it would be safe? Do they ever check any design? The answer is a NO.

I am quite confident  that a hoarding structure of this size would have been designed by a structural designer. What were the constraints he/she was working with? Is this an error of intent or an error ignorance? What was he/she thinking? The design wind  force, assuming a thumb rule 1.5 kN/m2 (~150 kg/m2) would be 2250 kN of lateral design wind force. The wind on that day was nowhere close to the design level. And yet it failed. And how!!

But why didn't any of us Structural or Civil engineers (in private or public service) call up the Municipal Authorities and warn them when we passed the structure? Is it because "they"  ignore us? Actually they don't. Every letter has to be responded to or at least discussed internally.  Is it because we have lost the ability to look at something, process it and make sense of its possible repercussions/risk? Or is it that we have become a world of callous citizens, hooked onto digital drugs and lost our connect with the world around us?

I'm suggesting something here. Anytime we see something odd in the built habitat around here, can we give a shout out at SEFI. SEFI posts automatically go on twitter and then maybe one of us who has written the tweet should tag their local municipal body.

Can we as SEFI become a pressure group to ensure safety and stability of the built environment? Sure there will be  "boy crying wolf" situations too but I think it is becoming increasingly necessary to call out potentially dangerous structures when we see them. It's our duty as Engineers. It's what SEFI is all about too!!

warm regards,
Alpa

[amitjha]

Thanks ma'am for your valuable inputs that clearly tells what structural engineering community can do, instead being mute spectaors to disasterous failures and ritual of shedding some tears for the lives lost. This hoarding was well publicised and its unlikely it was not noticed, only thing was missing that as engineering professionals (not as common man), we failed to pay any attention, failed to ask questions probably assuming that it beyond jurisdiction of engineers.

Situation in the country is such that for any structure standing , nobody will ask who designed it for for any structure failing , there is automatic questions as to "was it engineers fault" and often it assumed even without proper enquiry that engineers has been at fault. As a engineering community , how long we share the blame , the cursing , the negativity and bad publicity for sins that we didnt committed.

Thats because we have stopped speaking up, so engrossed in our work behind the scenes that we have forgotten to worry about public perception about profession. We must wake and act as watch dog by asking questions, warning authorities and at least we can flag such structure on this forum to act as warning signs for concerned authorities and pressurise them on doing their bit. Yes I must say as community we must take the role of being a strong presure group.
In a democratic country like ours engineers often complain about low fees and recognition issues. I must say we need to introspect. We must need to rise to defend the honour of the profession then only profession will bring us glory. Untill then we will keep facing default blame of failed structures where as in terms of value engineers earny least and interms of responsbility they have own up for faults not even committed by them.

I can say for sure if a structural engineer look at any structure coming carefully with curiosity we can often read loudsigns of probable distress than may soon result in a collapse. Ofcourse actual collpase may never happen in many cases with mercy of Gods of this country, but we should do our duty by asking questions and SEFI is the forum to do the same. Raising questions on structures that we may see, may help this society in many ways in forcing the building owners to find answers , to get structural audits done, getting notices from civic authorities and triggering remediation processes. Often that may save many lives..I am sure this is not expecting too much from our community. Life and death is in hands of God, lets introspect what we can do to reduce man made disasters. Even if contractors get punished by law of the land, those innocent lives lost for greed apathy mismanagement incompetence ..what ever you call, it can not take away the scras left on the families who lost their loved ones. It could be us, our family members too someday ..Apologies for sounding harsh

Once again thank you maam and vikramjeet sir for responding.

[francis chacko]

EXPERT STRUCTURAL ENGINEERS FROM SEFI OF MUMBAI SHOULD EVALUATE THE REASONS FOR STRUCTURAL FAILURE. WITH CALCULATIONS. THERE BY EVERY ONE CAN UNDERSTAND THE DEFICIENCY IN DESIGN.
K C FRANCIS


On Tue, May 28, 2024 at 2:32 PM alpa_sheth <forum@sefindia.org (forum@sefindia.org)> wrote:

[sushil_singh]

I think it's fairly irrelevant whether the hoarding was illegal or legal. What is important is that it collapsed and took innocent lives.
We live in a country / grade I city where the cost of structural engineering is declining day by day coming to what sometimes call as not even one tenth of cost ceramic tile. Even the labour unit which fixes an Italian marble gets paid 15 times than that.
One will always find someone to quote lower at the cost of skipping all the necessary inputs / checks as I really do not think given the same inputs engineers will arrive at different answers.
To quote Ashraf Habibullah on Linked in ( Founder & CEO of Computers and Structures,  Etabs)

[va]

Hi Alpa,You are right. Authorities are not interested in forcing all the safety regulations and design checks. Only after mishap blame game starts and the structure is declared illegal. There are thousands of illegal structures even buildings in MMR region and Mumbai. But no one is interested in the safety of common man. Why action is not taken against all illegal structures and they are tolerated is a very complex issue. Can we as SEFI and ISSE put pressure on Govt bodies against such malpractices? Can there be any provision to check the design of structures permitted by local bodies? 
Regards. 
Hemant Vadalkar 
Consulting Engineer Mumbai


On Tue, 28 May, 2024, 19:01 alpa_sheth, <forum@sefindia.org (forum@sefindia.org)> wrote:

[Ragothaman.s]

Hi all,

Very sad event. This can be avoided by eagerly checking the value engineering process.


The word economical design is to be replaced with value engineering.


Economical design is just cost point of view design compensating other important values to certain extent , where as value engineering is in all respects like cost, safety, adaptability, constructibility, socio suitability, eco friendly etc.


The design engineers or consulting companies should not adjust to satisfy client's economical perspective only.


MD,StructuralGuru
Engineering Consultancy & Trainings
www.structuralguru.in





On Thu, May 30, 2024, 2:27 AM va <forum@sefindia.org (forum@sefindia.org)> wrote:

[quote]            Hi Alpa,You are right. Authorities are not interested in forcing all the safety regulations and design checks. Only after mishap blame game starts and the structure is declared illegal. There are thousands of illegal structures even buildings in MMR region and Mumbai. But no one is interested in the safety of common man. Why action is not taken against all illegal structures and they are tolerated is a very complex issue. Can we as SEFI and ISSE put pressure on Govt bodies against such malpractices? Can there be any provision to check the design of structures permitted by local bodies? 
Regards. 
Hemant Vadalkar 
Consulting Engineer Mumbai


On Tue, 28 May, 2024, 19:01 alpa_sheth, forum@sefindia.org (forum@sefindia.org))> wrote:

      --auto removed--

Posted via Email

[bsec]

Dear AllFailure of Billboard in Mumbai has once again dented the image of Civil and Structural Engineers to the society at large. Such failures are not just accidents, nor acts of God (as one of the senior engineer, Shri Ganesh Kamat wrote in an article). They are clearly the results of human error originating from oversight, carelessness, ignorance or greed. Such failures not only results in loss of assets, which are only a small component of the total loss; it results in much greater national socio-economic consequences. Above all it dents the image of all of us Civil and Structural Engineers in the society. Unfortunately we are not learning enough from failures. The question that comes to mind here is a) Why failure occured? ; b) How could it be prevented? ; c) Who all are responsible for this failure? d) Is the forensic structural investigation done in this case to get into the root cause?  e) What should be done to prevent recurrence of such incidents in future? f) What legal liability governments have in such failures? f) What legal liability the geotechnical engineer and structural engineer have in such failure?


I think it would be great if SEFI forum can organise a panel discussion to dwell on the above issues 


As far as the technical reason for this failure, I think it is quite clear that the toppling of billboard occured due to foundation failure. Such structures are wind sensitive and the stability against overturning of such structures require proper attention. Either tension piles should have been provided or the foundation should have been taken to a depth, where the vertical load is sufficient to counter the overturning effect of wind.
This incident has also raised concerns about safety of all the hoardings pan-india. I think the authorities should wake up from slumber and commission safety audit of all such structures, as a preventive measure. The problem can be further accentuated in future due to impact of climate change, where wind forces can be unpredictably high, particularly in coastal regions.


We need to review our existing codes and standards to see whether these standards are sufficient to address the safety issues of such hoardings. Professional associations like IAStructE, may come out with a guideline for design of such wind sensitive structures. 


Best Wishes

Alok Bhowmick

FNAE, International PE (India)

Delegation Head (India), ING-fib 





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On Tue, May 28, 2024 at 2:31 PM alpa_sheth <forum@sefindia.org (forum@sefindia.org)> wrote: