Bi-axial Shear in a Concrete Beam with Torsion
Bi-axial Shear in a Concrete Beam with Torsion
(OP)
I have a concrete beam that is taking on a load that is creating torsion in the beam as well as bending and shear about two axis. I have the bi-axial bending worked out for the beam design, but I am having issues with the shear and torsion design. Can the design be looked at independently by using Vux and Tu, and then considering Vuy and Tu? My understanding of the truss model is that the shear carried in a plane is carried by the legs of the stirrup parallel to the shear and therefore the shears could be designed for separately.
Is this a correct interpretation?
Is this a correct interpretation?






RE: Bi-axial Shear in a Concrete Beam with Torsion
BA
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
I would think you would need to analyse the resultant diagonal shear on the section rather than the two separately.
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
But as it is a continuous loop then tension along the two sides will also cause tension in the top and bottom.
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
The modern code provisions for reinforcing for torsion are supposed to allow for the concrete internal "strut" action. Design provisions for torsion represent what is probably the most significant change between ACI318-63 and the later versions. Similar for Australian standard.
The tension in a stirrup varies as you go around the loop.
RE: Bi-axial Shear in a Concrete Beam with Torsion
Yes but that does not stop you modelling it as strut and tie to make sure you understand its behaviour.
Agree with the varying stirrup tension, about half of it gets taken out at each corner so the top and bottom tensions are only about half as much as the side ones but nevertheless it needs to be taken into account.
The complexity comes in when you are considering the effect of tension stiffening on the shear capacity.Biaxial shear for this would be different to uniaxial shear though I have never gone into this one in depth.
RE: Bi-axial Shear in a Concrete Beam with Torsion
RE: Bi-axial Shear in a Concrete Beam with Torsion
well, shell "core", shell zone.
and then "complicated" or "complex".
RE: Bi-axial Shear in a Concrete Beam with Torsion
BA
RE: Bi-axial Shear in a Concrete Beam with Torsion
i could not understand the ideas of designing beam due to biaxial shear and torsion
if anyone pleaaaaaaaaase have example or simple idea plz tell me