Background of Strut and Tie Method
Background of Strut and Tie Method
(OP)
What are the reasons for using a strut and tie model for deep beams? Will traditional design methods for flexure (Whitney stress block) and shear yield unconservative results for deep beams? Or does the strut and tie model just produce more economical designs?
I have never used strut and tie, but have a current project where a structure meets the deep beam criteria, and I'm trying to decide if it is worth the extra time to learn strut and tie to model it. Using tradional flexure design methods, the flexural steel requirements are very low.
I have never used strut and tie, but have a current project where a structure meets the deep beam criteria, and I'm trying to decide if it is worth the extra time to learn strut and tie to model it. Using tradional flexure design methods, the flexural steel requirements are very low.






RE: Background of Strut and Tie Method
http://www.gostructural.com/pg.asp?id=20
RE: Background of Strut and Tie Method
Strut and tie models are generally more economical when high shear loads are present. It may not be as big a deal for beams, but adding hairpins to slabs can be very costly.
Strut and tie models are more accurate for deep beams. Which is more economical will depend on the ratio of length to depth I believe.
RE: Background of Strut and Tie Method
It can be tricky to get started with, particularly when trying to analysis an existing beam. It can be easier for new beams where you can place steel to suit your model.
ACI puts out a publication, SP-208 Examples for the Design of Structural Concrete with Strut-and-Tie Models, that's quite useful.
It's definitely worth learning.
RE: Background of Strut and Tie Method
RE: Background of Strut and Tie Method
Regards,
![[pipe] pipe](https://www.tipmaster.com/images/pipe.gif)
Qshake
Eng-Tips Forums:Real Solutions for Real Problems Really Quick.
RE: Background of Strut and Tie Method
RE: Background of Strut and Tie Method
I haven't looked recently but most newer concrete textbooks should cover it. A Google search will bring up a lot of stuff on the Internet (searcher beware).
RE: Background of Strut and Tie Method
This design means the top face need not be reinforced, common to many concrete codes.
The advantage is if the beam is deep enough then shear links can be avoided.
I am pretty sure this concept pre-dates schlaich.
Robert Mote
www.motagg.com
RE: Background of Strut and Tie Method
RE: Background of Strut and Tie Method
RE: Background of Strut and Tie Method
Do you have a specific reference for this? Thanks.
RE: Background of Strut and Tie Method
As Qshake mentioned the CAST program found here: http://cee.uiuc.edu/kuchma/strut_and_tie/CAST/
is a good (though outdated and unsupported) free software tool for strut and tie.