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[Ashish Khatakalle]

Hello,

greetings!

Is there any difference Embedded anchor plate and normal base plate for design?
According to me both behaves same, the difference is only in shear force transfer in which embedded plate also plays the role in resisting shear force. but conservatively we can consider same behavior as normal base plate in which shear force is transferred only through anchor bolts. And for tension it behaves same as normal anchor plate. For checking thickness of the plate, it will behave same as normal base plate.  please correct if I am wrong anywhere in above assumptions.

[vikram.jeet]

Dear Er

If a steel column base plate with its steel column  is embeded in concrete pedestal , there is no need of anchor bolts.

However if steel base plate is embeded near to RCC pedestal top , the design needs to be done in same way as exposed base plate , as rightly expressed by you.

For taking advantage of shear , the base plate underside is provided with shear plates  in form of   +   to have shear resistance in both directions.

Embedment  without above stated shear plates , may improve shear resistance marginally to the extent of base plate width or Length multiplied by its thickness . All shear needs to be resisted by anchor bolts.

[vikram.jeet]

Mostly  base plates are kept 75mm to 150mm above plinth level , in sheds , PEB, and are exposed for painting /inspection/maintenance . Only Anchor bolts are embedded steel in concrete.

As stated in earlier post , resistance shear and bending tension is provided by anchor bolts for sheds buildings , but for Industrial buildings shear plates are provided beneath base plate.

It is seen in present days base plates of electric poles , base plates are kept above top of pedestal with anchor bolts transferring shear and bending tension, / compression . This protects from rusting of plates as rain water /moisture contact is eliminated.
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