AASHTO 4

[Lion06]

Sorry for the double post - I originally asked this is the wrong forum.

Does anyone know where I can find an example of seismic and wind loading for bridges per AASHTO?  I have the third Ed. of AASHTO (I know it's an edition behind for the exam, bit that is what it is at this point). I can't make heads or tails of it and I barely have time to finish tanning the codes I'm familiar with.

 

[strucguy]

There should be some examples in either six-minute solutions or the NCEES's sample exam booklet. You couldn't find any in there?

 

[strucguy]

The document below has a good example on evaluating seismic loads for a precast bridge. Hope it is useful.

http://www.pci.org/pdf/find/knowledge_bank/active/MNL-133-97_ch15.pdf

 

[Lion06]

Not so funny story - working 60+ hours per week for the last several months, I just started tabbing my codes/standards two weeks ago. When I realized how close the test was I made the decision (maybe incorrectly) that the little time I had left was better spent tabbing my codes than going through a reference manual, so I never ordered any of the study guides!

Even this weekend (with less than 3 weeks til the exam) was split between actual work and tabbing.

Thanks for that reference, I'll Check it out.

 

[strucguy]

Also, I found these examples very useful when reviewing the AASHTO code for the exam.

http://www.fhwa.dot.gov/BRIDGE/lrfd/examples.htm

 

[strucguy]

I am studying for SE-II myself. But, I am glad I don't have to deal with any of the AASHTO stuff for that.

 

[strucguy]

I would suggest buying 6-minute solutions atleast. It definitely helped me get into the exam mode. Also, the problems in the book are similar to what you will see in the actual exam. Anyways...good luck with your preparation.

 

[bridgebuster]

EIT - If you're using AASHTO LRFD you're 2 editions behind, but don't worry about it.

Wind Loading - Section 3.8
Seismic - Section 3.10

The references by strucguy are very good. However, the steel bridge example doesn't go into seismic, but the PCI example is good enough for a regular bridge.

Good Luck on the exam/

 

[JedClampett]

If you pass, will you change your name?

 

[Lion06]

Bridgebuster-
The AASHTO that someone let me borrow is AASHTO LRFD Bridge Deisgn Specifications 3rd Edition 2005 Interim Revisions. I'm hoping it's recent enough that I can get out of it what I need to.

I might change it, but not sure to what yet. StructuralPE is already taken.

 

[Lion06]

Sorry to be a pain, but where does it tell you how to calc the period (Tm)? I didn't see that in 3.10, is it in another section?

 

[BigH]

When I took my PE exam, being from Canada, if I didn't have the right "code" - I quoted the code I used . . .

 

[Qshake]

structuralEIT - The period is calculated as in physics. You will need the stiffness and tributary mass of a Bent or pier. Then the circular freqency, omega-n can b found by taking the square root of stiffness/mass. The fundamental period or natural period is determined by dividing 2*pi by omega-n.

For the definition of Tm, the m is for multimodal so if your doing a single mode analsys, m is equal to n.

Past exams the question is usually determine the transverse response or longitudinal response and not both. I've heard/seen (exam examples such as the Illinois SE study guide) longitudinal response more than others. If the pier is monolithic with the superstructure then you'll assume double curvature flexure in the pier for longitudinal direction and the stiffness is the summation of 12EI divided by height cubed. If the pier is not monolithic with the superstructure then you can use the simple cantilever stiffness, 3EI divided by height cubed.

Also, I answered your question in another post but appears it was deleted. You may want to check this link for seismic examlples.

http://www.atcouncil.org/pdfs/ATC492toc.pdf

else check more FHWA sites.

Good luck/

Regards,
Qshake

Eng-Tips Forums:Real Solutions for Real Problems Really Quick.

 

[Lion06]

QShake-
I did see your post in the other thread, and I bookmarked the page you sent. Thanks for the link and the explanation on Tm!

 

[bridgebuster]

A link to the FHWA Manual (2006) - Seismic Retrofit of Bridges (free download)

http://tris.trb.org/view.aspx?id=794156

 

[steellion]

The Structural Engineering Reference Manual put out by NCEES has good bridge seismic examples. I'm looking for help on wind for bridges myself.

SEIT, I would say that the SERM is just about a required resource for the exam. It is a great summary book, and really just a great reference to have after the test. Regarding AASHTO, you don't have to buy it, but I would strongly recommend getting the correct version. The code changes drastically from year to year.

 

[Lion06]

How do you get it without buying it? I don't know any bridge engineers, and I borrowed the version that I'm using.

 

[Lion06]

So I broke down and bought the SERM with overnight shipping. I should have a solid 12-16 hours with it over the next two weeks.

A couple things I noted by glancing at the beginning - it says a thorough review should be around 300 hours!!!!!!!! Is that true? I've spent about 16-20 hours tabbing and reading parts of codes that I've had little experience with. - I've done no working of problems whatsoever. Am I doomed here?

Also, it talks about bringing in BOXES of books. Is that common? I was palnning on codes standards and maybe salmon and Johnson, but not so many books that I couldn't carry in one trip.

 

[slickdeals]

I was palnning on codes standards and maybe salmon and Johnson, but not so many books that I couldn't carry in one trip.

Codes and references should suffice. Maybe an analysis textbook or some such. There is no point taking textbooks to the exam. You won't just have the time to flip through and figure out how to solve it if you don't already have an idea.

 

[Lion06]

That was my thinking Slick. Either you know it or you don't. I don't think you can figure it out during the test.