www.sefindia.org

[N. Prabhakar]

Dear Er. Harsoda Ji,

Thank you for uploading the YouTube video about the collapse of the old bridge.

It appears that the main deck slab, spanning between the piers, was simply supported.  As I said earlier, it is a failure due to maximum bending moment combined with maximum shear that occurred  when the wheels of the bus were at the points of failure, ie. at about 1/4 of span from end supports.  Because it is an old bridge, may be with poor maintenance,  the strength of the deck slab must have deteriorated very badly over the years. After the failure, The bus has moved from the point of failure to the extent possible.

These are my observations from the photograph and the video.

With best wishes,

N. Prabhakar
Chartered Structural Enginner
Vasai (E), Pin 401 208

[VPandya]

Dear  Er.  Harsodaji,  
For taking care of huge backlog on aging Roads and Bridges ( Infrastructure) , US Govt. creates  a new department.  We in India for our aging Infrastructure ( Roads & Bridges) may need to do something like this.  What they are calling " FASTLANE  GRANT  PROGRAM  OR  ONE-STOP  SHOP ".

From  latest American Society Of Civil Engineers (ASCE)  Smartbrief : dated  22^nd July 2016:  
With New Build America Bureau, Government Wants to Streamline Road Repairs and Infrastructure.  
New initiative by the Department of Transportation seeks to cut red tape and create shortcuts on the road to infrastructure repair.  
In an attempt to jumpstart repairs of U.S. roadways and begin addressing the huge backlog of infrastructure projects across the country, the U.S. Department of Transportation just announced the opening of the Build America Bureau. At a press conference  earlier this morning, Transportation Secretary Anthony Foxx celebrated the opening of the Bureau, which seeks to streamline the application process for federal funding and help public and private investors obtain loans, support, and expertise.  
The Bureau, brings together expertise from a variety of agencies, and offers a one-stop shop for access to loans, including the $800 million FASTLANE  grant  program, highlights Foxx’s belief in more effective government and a focus on public-private partnerships.It will help streamline access to existing funding sources and take advantage of recent funds provided by the FAST Act, the highway bill signed last fall.  

Web-Link :
http://www.curbed.com/2016/7/20/12235932/with-new-build-america-bureau-government-wants-to-streamline-road#comments

Regards.

Vasudeo Pandya P.E.
Structural Engineer

[B.V.Harsoda]

Structural awareness at each and every level of project management in construction project is very important for Structural safety.Negligence of safety measures leads to accident, below photo of Ahmedabad Metro is witness of this.

It is requested to Respected Er. V. Pandya Sir  from Ahmedabad for his expert comment in this issue.


Source link:-
http://epaper.divyabhaskar.co.in/index.php?editioncode1%2F

[VPandya]

Dear  Er.  Harsodaji,  
IN USA we ask FORENSIC Engineerig companies ( specializing in Investigating failures) to find the real cause of such failures. One very well known  Forensic Engineering company in USA  is " WISS JANNEY ELSTNER  ASSOCIATES ".   ENGINEERS like me who are dealing with only Structural Analysis and Design will not give their opinion on such failures.  However I can make a wild guess :
"Height of  only Reinforcement  cage without concrete  seems to be the problem. It is like Long Column effect ( Slenderness) of a Column which has only Tied  Reinforcement as a column section. " What AXIAL Stiffness (For Self Weight of  Reinforcement  Cage as  Load)  or FLEXURE Stiffness (For accidental Lateral Load during construction) is there in a TALL  Concrete Column with Tied Reinforcement cage only as Column Section.  Only  REBARS and no CONCRETE for such height."


I am sure there are ACI Guidelines ( Construction Tolerances) for such concrete Pier Construction .  


Regards.


Vasudeo Pandya  P.E.
Structural Engineer




  

[B.V.Harsoda]

Thank You Sir, I believe that, this incident is purely negligence of Safety Engineer to allowed such unsafe methodology in construction from contractor side and also from project manage ment authority.

[N. Prabhakar]

Re-written

[N. Prabhakar]

Dear Er. Harsoda,

It is really foolhardiness on the part of the Engineers at site concerned with this project to erect such a huge reinforcement cage to its position without having any lateral support.   One need not have a standard code or specification written for such an erection, but it is just commonsense one should apply for it.

N. Prabhakar