If column starter bars(lap splice) too short! 3

[IJR]

Where I am column joints are at floor level, not at midheight.

Seismic codes require that length of lap splices when column are joined at floor level be 1.5 times the basic anchorage length, as a punishment.

I have a situation where available starters are a ft short, satisfy basic anchorage length but not the 1.5 times increase.

What can be done to correct this situation without welding extra length to the existing short starters?

Thanx in advance
IJR

 

[JAE]

Would a mechanical anchor work? Lenton has its old stand-by "cadweld" product that can be installed in the field and requires no threading of the rebar (which cannot be done easily on a fixed bar in-place).

If the bars are not A706, I'd be wary about welding them for seismic response.

http://www.erico.com

 

[ishvaaag]

...except that introduce stress concentrations not especially good for a "seismic" embedment ina a column.

If the code is specific you can't but comply.
If you can allow on your liability the use, you could try to investigate the behaviour of the splices/embedments by any other technical information or code.

drill new anchors?

 

[Ron]

IJR...I agree with JAE. Would also add that the reason for lap is to assure development length. That can be achieved with a mechanical connection as well. There are several mechanical rebar connectors on the market that are not weld type.

 

[JAE]

Also....some of the mechanical connections have been ICBO certified for seismic use. The 1.5 factor would apply to LAP splices not necessarily mechanical splices. Mechanical splices are normally rated to about 1.25 times the strength of the rebar.