Two-Way Slab Edge Support 5

[Mike7117]

In the design of a two-way flat slab, would it be appropriate to consider that a "column strip" exists along the perimeter of a building that has a continuous 10" thick concrete foundation wall. If the slab is connected to the wall with dowels, would there not be a region of negative moment that is present in the slab adjacent to the wall? Or is it more practical to consider that the concrete foundation wall is much more rigid than the slab, therefore, the concrete foundation wall will resist the negative slab moment in this region.

 

[jike]

I believe there is still a column strip parallel to the edge beam. You still must consider the stiffness of the wall beam in determining the moments in the slab column strip.

 

[SERaymond]

Is important to consider the moment acting in the concrete foundation wall for the slab loads reactions, to prevent future problems on the concrete foundation wall.

 

[rapt]

Mike7177,

If the wall is acting as a support, then the slab moment in the area of the wall will be similar to the middle strip moment, so I would continue the 25% of the top reinforcement that has been placed in the middle strip parallel to the wall to the wall. The remainder of the reinforcement that would have been placed in the column strip is replaced by the wall.

 

[Tomfh]

No columns, no column strip.

 

[swivel63]

if it's a continuous support, there's nothing to worry about. throw some minimum steel if you want. in the orthogonal direction, there will be some negative moment. chapter 13 should have all of the factions by which to factor Mo in that condition.