A column is supposed to be a vertical member starting from foundation level and transferring the load to the ground. The term floating column is also a vertical element which ends (due to architectural design/ site situation) at its lower level (termination Level) rests on a beam which is a horizontal member. The beams in turn transfer the load to other columns below it. Such columns where the load was considered as point load. Theoretically such structures can be analyzed and designed. In practice, the true columns below the termination level [usually the stilt level] are not constructed with care and more liable to failure.

Hypothetically, there is no need for such floating columns – the spans of all beams need not be nearly the same and some spans can be larger than others. This way, the columns supporting beams with larger spans would be designed and constructed with greater care.

For Floating columns, the Transfer Girder and columns supporting Transfer Girder needs special attention. If load factor needs to be augmented (for Transfer Girder and its columns) to have additional safety of structure, shall be adopted. In the given system, floating columns need NOT be treated to carry any Earth Quake forces. Therefore entire Earth Quake of the system is shared by the columns/shear walls without considering any contribution from Float columns. However in design and details of Float columns, minimum 25% Earth Quake must be catered in addition to full gravity forces.

This way the overall system as some breathing safety during Earth Quake. However, Floating columns are competent enough to carry gravity loading but Transfer Girder must be of adequate dimensions (Stiffness) with very minimal deflection.

Though floating columns have to be discouraged, there are many projects in which they are adopted, especially above the ground floor, where transfer girders are employed, so that more open space is available in the Ground Floor. The transfer girders have to be designed and detailed properly, especially in Earth Quake zones. If there are no lateral loads, the design and detailing is not difficult.

There might not be paper detailing the diff. of adopting floating columns. You have to do a three dimensional analysis and be very careful at the joints where the floating columns meet the transfer girders.
IS Code:

Floating columns are not covered in codes , To a very little extent, Bridge column/pier on a well cap of large diameter may be treated as floating column with well cap acting as Transfer Girder However the well staining supporting the well cap ,being circular in shape, is highly strong supporting arrangement.

The comparison is only incidental since both building and bridge structures have different functionality.

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