Restraint Cracks at Basement Walls/Columns

[bbjafa]

The building I'm working on has perimeter basement walls with columns "inside" the wall at every grid. What I've learned before is since the retaining walls will tend to move more than the columns when the slab shrinks, cracks will develop where the basement wall meets a column or shear wall. Im wondering how you guys have dealt with crack mitigation that occur between retaining/basement walls and columns. One detail I've used before is to provide a gap where the retaining wall meets a column or shear wall but this requires separate pours and is a pain for contractors and architects hate it because they have to waterproof it.

 

[hokie66]

Is this a slab on grade or a suspended slab? It sounds like you are describing cracks parallel to the wall, but restraint cracking of suspended slabs is more commonly perpendicular to basement walls.

 

[HTURKAK]

this is a real problem when bldgs with multi basement storeys having thick perimeter walls. You may perform analysis for the shrinkage effects and the points and options you should consider ;

- The use of shrinkage compensating conc.
- Proper curing,
- Study the CJ locations,
- Provide EJ as necessary..

I will suggest you to look ACI 209 to get the concept.