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RE: TJI Trusjoist Beam Program review

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I also use TEDDS now (having dumped MathCad). The learning curve is difficult, but this may be the cause of their poor help files. I recently went through their tutorial (for 6.0) and was amazed how many questions it answered. I felt that I could jump in and design TEDDS sheets immediately with the tutorial at hand.
With this said, there is a tremendous amount of power in the ability of TEDDS users to create tables and lookup values. It is not clearly written and the advanced manual for programming TEDDS needs to be requested from their support line.
Although I wish that TEDDS could utilize the equation writer within Word so that the equations would look more like those I am used to in MathCad, I think TEDDS is a much better utility for our profession that MathCad is.
One other comment about MathCad. They currently have a special on professional upgrade for $199.00. I also understand that MathSoft sold out to another company and I don't know what they intend to do as far as future work to support the engineering industry. However, users of TEDDs can now obtain their upgrades via a subscription service that is, in my opinion, very reasonable - about $12.00 a month paid annually. This insure CSC with development funds while keeping you updated with the latest releases and support.
As those who will soon find out on the Structuralist (when I have more time to complete my latest writting), I am not in favor of subscriptions with software because of the volitility of the industry to those of us in small or independent offices that can not always count on a continuous cash flow. Still, at this stage of the game, CSC's renewal subscription rates is an excellent value and while the software has a learning curve, there is a tremendous hidden ability that most of us can see by using some of their automated templates.
I am now a devoted TEDDs user and don't mind admitting it!!
-----Original Message-----
From: David Merrick [mailto:mrkgp(--nospam--at)]
Sent: Thursday, September 26, 2002 12:03 PM
Subject: TJI Trusjoist Beam Program review

I tried to use the truss joist beam program (6.02)

It is not worth using. Please further comment if there is more to be said or corrected.

To check one complex loaded beam (a reason to use a program) with seismic options. We need to run the same program eight times. To check for the Wind we need to run the program an additional four times. To print out the results, 2 pages per run results in 24 pages of printed calculations.

I have found Pframe to be able to run all load cases at one time. The load cases and varying section properties can be stored for the next analysis.

I have heard Enercalc also reduces the paper work. As I recall, there is no option for vertical reactions for earthquake.

I have TEDDS, but it takes on a life of its own to learn.

For the alternative basic load criteria in the 1997 UBC and having seismic vertical reactions. Assuming all seismic input is reduced by 1.4

TJI checks the following three equations...

    1. D+L+Lr
    2. D+L+E (increases stress allowable 1.33)

      And the following are not checked...

    3. Snow option not reviewed, someone, please comment
    4. Snow option not reviewed, someone, please comment
    5. Snow option not reviewed, someone, please comment
      1. 0.9D+E
    1. 1.2D+0.5L+Em (to achieve the ultimate stress check reduce loads by 1.33/1.7)
    2. 0.9D+Em (to achieve the ultimate stress check reduce loads by 1.33/1.7)

Additionally, the seismic loads are not checked for the reversed direction. The Em equations are needed or else we are not in a zone 3 or 4 and there are not vertical seismic reactions on a beam. Equation 12-23 can be run for wind but, like seismic, not for the reverse direction and not for uplift resistance.


David Merrick, SE