How to check column

Hi all, one of my friend on FB showed me this picture and asked me, what is the probable causes of it and how to prevent such situation.


The thing which seen in above picture is just happened due to improper supervision at execution site.

Joggling reinforcement bars in such a way is just like a criminal activity done by a civil engineer either by knowingly or unknowingly.

If you find there is no cover or very less cover to column reinforcement bars, please show it to ur structural consultant before doing any action over it.

If possible you may increase the section of column on that particular floor. I am not expert but in general joggle should be made in ratio of 1" in 2feet length ( i learnt this from the most senior persons having 35+ years experience, they also may be wrong but this they called it as safe.).

so avoid sharp joggling of bar.

To prevent such situation you must try to understand what are the possible reasons resulting to this situation.

1) no checking done by engineer or supervisor before casting.
2) checking was done before concrete but during concrete cover to reinforcement was displaced and reinforcement got moved from its location ( i dont know if you have observed or not, unskilled labours takes support of column reinforcement to lean out to the external faces and does lot of things)
3) Reinforcement bars was not checked immediately after concrete for its correct location and cover to it.

 Friends once we know what is causing this problem, we are ready to eliminate this by taking timely action over it.

1) Cover to the reinforcement of column should be checked before concreting and immediately after concrete. ( if you do like this or atleast you make sure your supervisor does this without fail every time. i will assure you, you will never see such problem again )

When you cast a column also adopt this procedure of checking cover to reinforcement and check verticality of column before and immediately after concreting.
Further to this i will also like to add more to create awareness about columns.

My seniors told me once upon time about the columns.

Now we bent the stirrups hooks at 135 degree. earlier they were use to bend it at 90 degree only.

but after gujrat earthquake, from the studies they found that, all columns failed due to opening of stirrups as they are bent at 90 degree.

after that day all consultant included 135 degree bend at hook in all their designs.
 Friends but still i see lot of peoples are not aware about this or they know it but doesent take any action over it. so i request all to act like a responsible engineer and if you see something is happening in wrong way, raise your voice to stop it and correcting it. 

If you like it please give your comments i will be happy to here from you peoples.