pencil & paper vs. software for calcs 2

[bjb]

I'm wondering, how many structural engineers mainly rely on software like mathcad for their calcs, versus how many mainly rely on a calculator with pencil and paper?

 

[SacreBleu]

IMO, Enercalc was really a revoultionary and ingenious product when it first came out. Over the years, it has improved only slightly in technical quality. (Discounting the inevitable evolution from Lotus123-based to DOS to Windows version)

 

[mrMikee]

Years ago when I got my first FEA program I remember reading in the manual something to the effect that "the fact that a computer program runs through to completion does not necessarily mean the output is correct." This is still good advice today in my opinion.

-Mike

 

[vmirat]

Just an observation here. I find it interesting that those projects that are of immense complexity, such as huge multistory buildings, can't be done by hand. They would take too much time and hand calculations would introduce too many chances for error. The projects that need accuracy the most are the ones that depend on computers the most. And the future of structural engineering doesn't look like it's going to get any simpler (just look at the wind load requirements in ASCE 7-02!).

So, if it's good for goose, it's good for the gander? Why accept the computer stuff on the big projects without question but question the stuff on the little projects? Seems contradictory to me.

I personally do both - hand and computer (including purchased software and spreadsheets that I have developed in Excel). I would use more computer programs if I could afford them!

I remember when we were first allowed to use calculators in high school. My father would not let me use my calculator at home without doing the problems by hand first. Today, calculators (and I'm talking fancy graphing things) are required by high schools, even down to a particular model and manufacturer.

This debate almost sounds like a cultural thing. The old guys (like me) grew up with slide rules and calculators that might do square root. Kids today are growing up with technology that boggles the mind. They have implicit trust in this stuff to the point that questioning it's usefulness is like questioning the value of a car (duh!).

We need to accept that fact that technology is here to stay. As a community, we should be developing training methodologies for new engineers that utilize these tools effectively instead of forcing hand calcs as a check against the "machine". At the same time, we need to lobby the software companies to develop programs that we can use instead of what makes them money.

 

[archeng59]

I agree that computers are necessary. they are a wonderful "tool", not a substitution for "brain". in my opinion, computers and associated software are sophisticated calculators. they are no "smarter" than my pencil. that's what I'm trying to make my engineer interns understand.

 

[mikedmiston]

I do 90% of my calculations by hand, and my boss keeps wanting me to use EnerCalc. Each beam he uses another sheet in EnerCalc and his calcs are twice as fat as mine. He says the fatter the packet the easier it is for the client to write the check. I think a client won't compalain about the hours when they see the calcs were done by hand.
We do all wood construction, vertical and lateral. So the calc's are easy. For steel beams I'll use enercalc because of the database, otherwise, I use my trusty TI-83 with self-written programs for beams.

 

[lsmfse]

We stress to all our engineering interns that software is a tool that can be used facilitate structural design. However, we require hand calcs in tne early months of employment so that I can see that they understand what thier diong. Recently, I reviewed some Enercalc output by one of the engineers and noticed he forgot to change the load duration back to 1.0 when designing floor beams. These things can easily be overlooked by young engineers.

 

[whyun]

Older engineers have developed an intuition for sizing through their experience and having solved problems by hand when they were young engineers. Without having developed a "sense" for what sizes appear adequate as opposed to obnoxiously over/undersized, it is dangerous for young engineers to trust a computer output without a senior engineers review/comment.

I am not against technology, in fact, I am completely in favor of using computer as a tool (as much as we can to minimize design time so we have more money left over after putting food on the table). What I object to is blind trust in computer output.

Project managers, and senior engineers alike, are often pressured with meeting deadlines. They don't have time to look over every input/output that design engineers produce. Only with proper training, one can gain confidence in young engineers' work and ensure their career development.

At this stage in the structural engineering field, a good balance of hand calcs and "readable" computer output are essential for our own sake as well as the public we serve.

 

[SlideRuleEra]

http://www.slideruleera.net/MaintainSharpInstincts.pdf

http://www.SlideRuleEra.net

 

[mrMikee]

SlideRuleEra,

That brings back memories. I had a post Versalog that I think cost about $30 which was a lot of money for a college student back then. Thankfully we don't have to use these anymore. I'm glad you posted that however. The next time I'm grinding through some code to get a program to work it might help to think back to my sliderule days.

Thanks,
-Mike