Tension force in a tank wall

I have modelled a rectangular concrete tank in STAAD using plate elements and need to do some additional calculations to check the crack widths do not exceed a given value.

I can get a contour plot of the bending moments in the walls but when the tank is full and there is no backfill to it, there will also be a tensile force in the walls.  Can I do a contour plot showing this tension?

I thought plotting SX or SY would give the tensile stress, and if I multiplied this by the section thickness it would give a force in kN/m.  Doing this gives a tension of around 750 kN/m in one of the walls, whereas a design based on PCA guidance says it should be about 200 kN/m. 

Parents
  • Your interpretation is correct. Depending on how the local axes for the plates are oriented, the SX or SY would give you the tensile ( /compressive) stress. You can multiply that by the thickness of the wall and a width to get the tensile force over that width. For example width can be considered as 1 ft or 12 inch if you want to find the force over a 1 ft width of wall.



    Answer Verified By: Peter Everett 

Reply
  • Your interpretation is correct. Depending on how the local axes for the plates are oriented, the SX or SY would give you the tensile ( /compressive) stress. You can multiply that by the thickness of the wall and a width to get the tensile force over that width. For example width can be considered as 1 ft or 12 inch if you want to find the force over a 1 ft width of wall.



    Answer Verified By: Peter Everett 

Children