Effective Sliding supports? 4

[IJR]

I have to consider this case seriously. A girder longitudinaly free to slide at a support but A LARGE REACTION has to be resisted at the same support in the other direction

Here in plan
P
X-------*----------free this direction
.
.200kips
.Y

So point P is a support with 0 reaction along X but large reaction along Y

What support systems do my pals use for such a situation?

Respects

IJR

 

[ishvaaag]

The modern trend would be to use elastomeric pads of one or other kind, normally with embedded plate armor. This exceeded, rollers or set of rollers with a limit to displacement beyond any expected lateral movement and with vertical clamps if required may be used. Plates coated with teflon may or may not advisable as an alternative.

 

[RiBeneke]

I agree with ishvaaag.
Depending on circumstances a sliding or an elastomeric (rubber) bearing may be preferred. If you choose rubber, then the required transverse stiffness or resistance to displacement can be achieved by placing additional rubber bearing pads vertically (sandwich on edge) on each side of your girder at the bearing end.

 

[JAE]

Agree and also...

I've seen girders with bearing pads as they mentioned above but with an added set of steel brackets on either side of the girder, anchored to the support, which allow the longitudinal movement but resist the lateral. You can allow the girder to simply rub against the brackets, or detail in slide bearings (teflon) to allow easier movement.

 

[thaidavid]

IJR,
An old-time solution used under the support saddles (pads) of horizontal storage tanks (which move thermally) is to trap the base plate against welded guide angles in one direction. The base plate rests on a fixed steel liner plate, with a liberal amount of grease between the two to promote sliding. Zerk fittings in the top of the saddle base allow for periodic replenishing of the extruded grease. I hope this helps.
David