High point loads on continuous basement walls
High point loads on continuous basement walls
(OP)
Hello!
I have some questions regarding continuous basement walls, loaded with high loads from column.
The question is how to deal with the high vertical point loads.
- Is it correct to adopt a strut-and-tie philosophy and reinforce for the horizontal tensile forces in the top of the wall (and some further down aswell)?
- Is it needed to calculate reduced node capacity with regards to biaxial stress state (CCT-node)? Or can you adopt a 'column representation' and calculate the compressive capacity in the wall.
Would be thankful if someone has any ideas on this!
I have some questions regarding continuous basement walls, loaded with high loads from column.
The question is how to deal with the high vertical point loads.
- Is it correct to adopt a strut-and-tie philosophy and reinforce for the horizontal tensile forces in the top of the wall (and some further down aswell)?
- Is it needed to calculate reduced node capacity with regards to biaxial stress state (CCT-node)? Or can you adopt a 'column representation' and calculate the compressive capacity in the wall.
Would be thankful if someone has any ideas on this!






RE: High point loads on continuous basement walls
1) I like strut and tie as you've shown it which is as a means of dealing with load spread, independently of other stuff.
2) A column representation would be exactly my approach here.
I like to debate structural engineering theory -- a lot. If I challenge you on something, know that I'm doing so because I respect your opinion enough to either change it or adopt it.
RE: High point loads on continuous basement walls
Column reinforcing may contribute to additional cracking... How high are your bearing stresses?
Dik
RE: High point loads on continuous basement walls
RE: High point loads on continuous basement walls
On a recent project, I went with your approach 2. I treated the wall as a column and placed a spread footing directly under the point load.
I would have no objection to distributing the load horizontally across the wall, provided the wall is tall enough to get relatively uniform loading with the loads spreading out at 35deg +/- from the point loads. The foundation would then be a strip footing, wider than you'd have with "approach 2".
Your sketch shows a pretty tall wall, I have a hard time imagining that tensile reinforcing is required. I always think of these in terms of shear failures along a 35deg-45deg line. If you wall is deep enough to distribute the load via this mechanism without any shear issues, do you need tensile reinforcing?