Intro to Frame Design

[smokiibear]

I have very little experience with steel frame design. Further, I have virtually no access to anyone that does. Could anyone recommend any references for learning frame design. I'm looking for a thourough step by step guide with sample designs.

I've used risa 3d a number of times for timber design, though configuring boundary conditions is usually very challenging. I'd love to find references for the basic frame design using something like risa, as well as reference for designing connections. Using the ASCI 13 manual without much experience has been quite a challenge too.

Thanks for your help ahead of time.

 

[msquared48]

How much exposure to running the numbers do you have?

Are you familiar with the Portal and Cantilever methods of the early last century, as well as Moment Distribution, and the concept of the P Delta effect?

You can't just plug the numbers in without a feeling for it.

Mike McCann
MMC Engineering

http://mmcengineering.tripod.com

 

[smokiibear]

I have had limited exposure. Most of my exposure was classroom based, over 7 years ago. That exposure included 3 finite element classes (where I wrote a program to analyze my mountain bike with shocks), included sap2000 for bridge disign and elementary design for steel and concrete buildings. Being several years ago...and primarilary working with wood, this experience is a vague memory...so I need some touch up.

I understand in very elementary manner portal vs cantilever.
I have worked on moment distribution problems...but a number of years ago...and understand P-Delta just fine (not necessarily where it needs to be computed and where it's secondary effects can be ignored), but conceptually.

So, I appreciate your warning...andI also look forward to answers to my original question.

Thanks.

 

[frv]

If your ultimate goal is design, rather than simply getting a feel for the numbers, there is a bit of a complication. With AISC specifically, you cannot separate the analysis method from the design method. That is, the way you analyze a frame depends on whether you will use K=1 or not, and whether you will approximate 2nd order effects or analyze them directly.

If, however, you just want to get a feel for it, then any structural analysis book will have several methods, including approximate methods (much simpler, less accurate) to determine the forces in your members. I think Hibbeler does a good job of presenting the information in a simple manner. I have the 6th Ed., and I've run into several errors. Perhaps the 8th Ed has resolved these errors.

 

[paddingtongreen]

smokiibear, you sound as if you think the main problen is learning a computer program, it is not.

At this point, we don't know what you want; honestly, it sounds to me as though you are looking for "black box" processes, processes in which if you follow the rules, out pops a perfect design.

If you want to understand the behavior of structures under load, and then how to use the computer based tools for the analysis and design, we will enjoy helping you, but most of us will draw the line at giving you the black box. I think that most of us don't know of any black boxes.

I recommend that you learn structural mechanics followed by one of the programs. There are a number of freebees, oldies but goodies, that cover manual calculations. As you work through an example by hand, you can check it with a computer tool.

I found this on the web that may be a reasonable start, it includes a discussion of the "LRFD Vs. ASD" argument, to which, frv refers:

http://www.aboutcivil.com/design-of-steel-structures.html

I found this one, old but truth is still truth;

http://www.thecivilengg.com/documents-selfupload/structural-ebook/structural engineering'a'.pdf

Michael.
Timing has a lot to do with the outcome of a rain dance.

 

[smokiibear]

wow...Just for clarification, I'm not looking for a black box at all. I'm starving to understand on everything I do. Let me reiterate my questions: (1) any good references for working with Risa 3d, (2) any good reference for frame design, (3) any good refences particularly for design of connections.


Thanks for the links. Will review.

 

[smokiibear]

Let me add a little to that last post. I have worked in an environment in the past where most of the folks I worked with didn't know much about what they were talking about, both in civil and strucutral field. I was continuously looking for answers and asking questions.

Unfortunately, my experience is limited to wood frame design. As opportunities come up, I have struggled through the years to understand steel, concrete, and masonry due to my limited access to engineers around me. That has led me to post the question in the first place.

A few years ago I sought everywhere I could for pool design....even called old professors at the universities trying to find some guiidance. I couldn't come up with anything...so I eventually laid down the effort (at least for now).

I have used risa 3d for a number of years, usually 2 or 3 times a year. Everytime I would call Risa, or search for answers online, I seemded the information I could find seemed to conflict with eachother (especially regarding boundary conditions). Phone calls to risa even resulted in conflicts as their tech support would say one thing while their webcasts another.

Again, my reason for posting a request for help is to grow and really understand how to design.

Any help and pointers would be greatly appreciated.