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Re: Bridge Bent Cap Design Programs

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While I was looking into moving up and away from CAP18, I decided that I wanted a more powerful program that wouldn't only analyze but design bents as well.  I considered RC Pier LA, recognizing that it is indeed a very powerful program, but discounted it when I found out that it doesn't design inverted-T's.  But what you are saying is that you use this program to only analyze an inverted-T bent cap and then you design the cap as you would had you used CAP18?  Then the benefits you get from RC Pier LA is that the program calculates and applies all loads automatically, including transverse loads, which negates the need for a 2D/3D analysis program.  Additionally, it also provides column and footing analysis and design.  Sounds impressive, indeed.  But it is REALLY expensive.  Hence my hesitation at just running out and buying it and why I won't let this issue die...
 
I'm thinking out loud, here, and would still appreciate input from all of you bridge engineers out there.  I'm a young engineer who's been put in charge of starting up a structural design group at my company (starting small, obviously).  I'm still struggling with all the overwhelming choices of software out there.  I've been doing it one way for over 5 years, and am reluctant to change.  But by purchasing a program like RC Pier LA, I could conceivably do away with STAAD, CAP18, RECOL and all the manual spreadsheets I have set up to calculate bent loads!  (Which of course would serve well as checks...)  Lastly, it is capable of LRFD design, which will be great if/when TxDOT gets around to doing that.
 
Nora Miller
----- Original Message -----
Sent: Thursday, June 07, 2001 12:27 PM
Subject: RE: Bridge Bent Cap Design Programs

Neither does Cap18.
 
For inverted-tee caps, generally the procedure that was published about 15 years ago, by Richard Furlong of U. Texas, is followed (I forget the name of the publication, but you probably have a copy of it anyway).
 
The problem with that of course, is that it uses very outdated procedures for such things as torsion. But much of what he has done is valid.
 
FWIW, I emailed Furlong about two years ago, asking if he was ever going to update his procedure. He replied that he had been intending to do so for some time, that he realized it stood in need of improvement and updating, but he was afraid that death or retirement--often one and the same--were going to intervene before he ever got around to it.
 
Oh, and my experience is that TxDOT HAS no "approved software" per se. Many of the TxDOT engineers are just as contemptuous of CAP18 and PRSTRS14 as you are. As long as you are doing it right, and are willing to seal your work, they will accept calculations done with appropriate methods.

William L. Polhemus, Jr., P.E.
Polhemus Engineering Company
Katy, Texas
Phone 281-492-2251
Fax 281-492-8203
 

-----Original Message-----
From: Nora Miller
Sent: Thursday, June 07, 2001 11:26 AM
To: seaint(--nospam--at)seaint.org
Subject: Re: Bridge Bent Cap Design Programs

I am also looking into moving up (almost ANY move would be up) from TxDOT's antiquated program, CAP18.  One of the major drawbacks of RC Pier LA is that it does not design inverted-T bent caps.  I've been designing bridges for TxDOT for almost 5 years, and the majority of my bent design has been with inverted-T's.  Also, take into account that in most cases TxDOT states in their contracts that work is to be done with their approved software...