How can we strengthen column beam junction ?

How can we strengthen column beam junction??

In site we casted plinth beam and column, while testing it's gives only 20 N/mm2 so decided to strengthen.

So can any one suggest some Strengthening methods for column -beam junction.
Required strength was 30 N/mm2 but we got only 20 so need to strengthen it..
 

amd007

Elite Member
You will need to grout the core with low viscosity epoxy grouts to first fill up the pores in the concrete once this is done you once again check whether desired strength is achieved with grouting.

A series of grouts need to be used starting with very low viscosity grouts followed by higher density grouts ( This is a very specialized job which cannot be achieved by your local workers) once the grouting is completed again a test is conducted to ascertain whether the desired strength is achieved.

If still it's not achieved then you will have to resort to FIBRE WRAPPING TECHNIQUES where you can certainly achieve the criteria which you are mentioning.

The reason for mentioning the 2 steps was COST so if your strength is achieved with grouting then there is no need to fiber wrap the members.

Note: This is a specialized job that is executed by professionals knowing the job and in particular know how to design it.
 
You will need to grout the core with low viscosity epoxy grouts to first fill up the pores in the concrete once this is done you once again check whether desired strength is achieved with grouting.

A series of grouts need to be used starting with very low viscosity grouts followed by higher density grouts ( This is a very specialized job which cannot be achieved by your local workers) once the grouting is completed again a test is conducted to ascertain whether the desired strength is achieved.

If still it's not achieved then you will have to resort to FIBRE WRAPPING TECHNIQUES where you can certainly achieve the criteria which you are mentioning.

The reason for mentioning the 2 steps was COST so if your strength is achieved with grouting then there is no need to fiber wrap the members.

Note: This is a specialized job that is executed by professionals knowing the job and in particular know how to design it.

What kind of test are you talking about??
Can u mention any names
 

Dnyan Deshmukh

Staff member
The decision on the method of the strengthening should be taken from structural consultant only as he takes the guarantee of structures designed by him.

Column Beam Junction is most important part of the structure where maximum forces are acting on, plinth beam level is of high importance.

There are many ways to strengthen it like wrapping in carbon fibres, sand-witching between steel plates, jacketing the junction, injection grouting and many more, each comes with its own additional cost which could be highly expensive.

You can also wait for more time and do NDT tests on the concrete to know surface hardness, soundness etc. and also do test additional sets of concrete at say 35 42 days to check strength gain.

Some times it also happens, the person who is doing cube casting activity, haven't done correctly or sent the cubes to curing tank with delay of day which could give you a false results.
 
The decision on the method of the strengthening should be taken from structural consultant only as he takes the guarantee of structures designed by him.

Column Beam Junction is most important part of the structure where maximum forces are acting on, plinth beam level is of high importance.

There are many ways to strengthen it like wrapping in carbon fibres, sand-witching between steel plates, jacketing the junction, injection grouting and many more, each comes with its own additional cost which could be highly expensive.

You can also wait for more time and do NDT tests on the concrete to know surface hardness, soundness etc. and also do test additional sets of concrete at say 35 42 days to check strength gain.

Some times it also happens, the person who is doing cube casting activity, haven't done correctly or sent the cubes to curing tank with delay of day which could give you a false results.