LRFD Footing Shear Design
LRFD Footing Shear Design
(OP)
How do we properly design for one way shear in an abutment or retaining wall footing using the latest AASHTO LRFD specifications? We have found so far that the AASHTO LRFD specification requires a much greater thickness of footing to meet the shear requirement than the the latest standard AASHTO specification. It doesn't make a lot of sense to have a deep footing for a 30 foot tall retaining wall when normally a 3 to 4 foot deep footing would work using the standard specification.
Thanks.
Thanks.





RE: LRFD Footing Shear Design
In the strut and tie model, just as in a truss, there is no shear per se, just axial loads in the assumed members.
curvbridger
RE: LRFD Footing Shear Design
You raise a really good point. Because of the code change, do we revisit the structures designed under the old code and "upgrade" them? No! (Assuming there is no major flaw in the structure.)
When significant code changes come along and result in a new design that doesn't seem to make sense based on older codes and COMMON sense, shouldn't the new code be revised? How do all these older structures stand up? Every provision of a new code doesn't always point us in the direction of progress, there has to be some common sense too.
RE: LRFD Footing Shear Design
Just as a matter of interest; @ 30' high, why aren't you considering a counterforted wall rather than a cantilevered wall that I assume you are designing? I presume the economical minimum height for counterforted or buttressed walls is somewhere in the vicinity of 28'???
Regards,
RE: LRFD Footing Shear Design