RISA Foundation Overturning 1

[IsaacStructural]

Anyone familiar with retaining wall design in RISA foundation? How does the program handle complex wall geometries, for example, walls that have 90deg turns. I'm wondering, does the program account for the wall spanning between adjacent wall segments, and the increased overturning resistance these walls provide?

M.S. Structural Engineering
Licensed Structural Engineer and Licensed Professional Engineer (Illinois)

 

[FlashSet]

Solve this problem by creating a small scale model in RISA and investigate the results yourself.

I would strongly encourage you to undertake this simple task. You will learn a lot about how RISA (or any other computer software) functions.

 

[IsaacStructural]

I actually don't own RISA foundation and don't have access to the program right now. I anticipate having the program in the near future and I was wondering if this program would be useful for a problem I've got coming up. In which case I might hold off doing the problem by other methods (hand).

I actually investigated the literature of the program and it appears it does not deal with the global stability of a wall system like I described, it seems it can't truly design counterfort type walls and will always treat them as cantilevered.

Sometimes I ask questions in multiple locations (in this case I asked RISA directly, asked here, and searched the program documentation). I can't be sure which will provide the best or fastest answer to my problem before hand. Perhaps someone on here had the same question and new the answer and could provide it in 30 seconds, I don't know.


M.S. Structural Engineering
Licensed Structural Engineer and Licensed Professional Engineer (Illinois)

 

[msquared48]

To my knowledge, RISA Foundation does not account for corner conditions.

You know though, I would just continue the same reinforcing and footing size to the transverse wall. Who is to say that in some time in the future, that the transverse wall would not be removed for an addition, or weakened with penetrations, for whatever reason?

Therefore, I would reccommend that each wall stand alone, thinking of the future. The extra reinforcing and concrete is a small price to pay for flexibility of design.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[IsaacStructural]

Good points Mike. I'm thinking I will just do the design by hand, though I could build a RISA 3D (not RISA Foundation) model that could get the stresses/moments correct. It wouldn't do the design/code checks properly though.

M.S. Structural Engineering
Licensed Structural Engineer and Licensed Professional Engineer (Illinois)

 

[JoshPlumSE]

RISAFoundation does not account for interaction of the walls at corner intersections like that. Each wall is viewed as an individual wall.

FWIW, there is a Demo version of RISAFoundation available on our website that you can try out and experiment with. It's got limitations related to printing and saving. Maybe some limitations on the materials that you are allowed to enter, but it should give you a pretty good idea about whether or not the program would be useful for you.

http://www.risa.com/forms/demo_request.html

On warning though. The website seems to be running kinda slow today. So, our internet host may be experiencing some issues that cause the download to run really slowly.