hand calculations

huangyhg

hand calculations
i am curious how many people still do hand calculations for structural analysis and steel design, or know of someone who does?  things like moment distribution, combined stresses, and so on.  when are hand calcs appropriate, or not.  does anyone have opinions about this?
just wondering.
best regards,
-mike
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i only use the computer to check my hand analysis (i prefer slope deflection when i can use it).  i have a couple of utilities that i programmed into my calculator, but once again i only use them to for preliminary analysis.  once in a while i'll do an indeterminate analysis on cframe.  everything else i do by hand.  i can look at my calculations years after i did them and immediately understand what i was doing.  even the mistakes are obvious.
the engineers who review my work (in-house and the occasional plan reviewer)seem to appreciate the hand calculations.  not so much "black box" engineering.  plus with hand calculations, i usually do sketches that explain the design.
i'm afraid i'm the last of a breed.  i can get away with it because i'm a senior level employee, but the younger engineers are afraid hand calculations and sketches slow them down.
it just varies according to what you are doing.
for a one-time simple project, hand calcs are fine.
for simple calcs that require references and explanations, etc., i've actually made "word" documents, and it's fairly quick to go through and change the numbers for the case in point.
spreadsheets work great for lots of things- anytime you're doing the same basic thing several times over.  i've done a couple using visual basic (took that as continuing ed for pe licenses), and that can be pretty cool.
i replaced my hand caculation by creating several excel sheets which can analysis multi span beams or slabs using moment distribution concept
also design a pt & rc concrete with a lot of functions , and currently it is my basic tools in prelaminary design befor going to a fea software.
from while to another i trying to improve these sheets and i found it a good replacement for the hand calculation.
for small one time calcs and simple beam designs, hand calcs are great...but for analyzing and designing 20+ story buildings within the schedule expected by today's clients it is next to impossible without using building analysis software to automate the process.  garbage in garbage out is as true as always but these programs do greatly increase the efficiency of design provided they are used correctly.
i am a relatively young engineer, 3 1/2 years since my first degree.  i generally do quite a bit by hand.  all of my silo and bin designs are by hand.  it just depends on what i am doing and how exact i need to be.  as a minimum i always do a back of the envelope type calculation to check the computer.  many of the more complex structures require computer analysis because of the large indeterminate nature of them.  i have always thought that i was the only person with my experience level that did calculations by hand.  my supervisor (he's 51) still does a lot by hand, so i was glad to jump on the hand calculation experience since he doesn't jump down my throat when i do it.  another young engineer i know has done very little by hand.  when he started with his firm they started teaching him all the little software programs they use (nothing about how to get the outputted results).  to me he seems somewhat useless because his analytical skills are weak and he doesn't have a good feel for what is going on.
software programs are great for improving efficiency, but hand calcs are necessary, not to "check the computer" generally, but rather to check the user in my experience.  i wouldn't want to hand calc a 20 story building, but i would be interested in hand calcing a simple truss, making certain i'm getting an accurate result and then making the leap to say the 20 story building analysis was correct.  aggman's story of the "useless engineer" is too frequent.  universities aren't teaching applications the way the used to and then we take young engineers, give them a computer, and rely on their results without providing adequate training or support.
ok, off the "bandwagon"...nice to see some people still re  
hand calcs are necessary when you work for someone who doesn't buy software.  almost evertything i do is by hand calcs or by a spread sheet i have invested hours in creating.  i also will take a look at quick numbers to check computer results.  i believe either hand calcs or software are fine as long as you aren't using the software to do something you don't understand or couldn't get yourself in an appropriate amount of time.  what's hard about the hand calcs though is trying to produce them for a project budgetted as though i had software to do everything.  i am also relatively new in the field with a little over 3 years of experience.
i do most of my work in mathcad, which is essentially an electronic hand calc, in that the formulas are right there and can be annotated by text.  in most worksheets, i use calculus to develop shear/moment/deflection diagrams for simple and continous beams, and retaining walls.  the time invested in developing the worksheets is saved upon reuse.  some structures require black box software, like a 3-span continuous bridge with composite stringers (varying moment of inertia) and moving live load.  if anyone has a hand solution for this, i'd love to see it, as i hate using software that i didn't write.
thanks for the comments.
i still do a lot of calcs by hand but will use software when i can.  i have been writing programs in basic and visualbasic for about 20 years, and i like vb, but these are very specific in function.  about two years ago i bought a calculation program and find that now i am doing less with vb and more with the calc program.  these programs (these are several good ones) are more of a free form type of calculation sheet that is something like using ms word but with the ability to solve equations.
it has occurred to me however, that even though i am using software, my approach and thought process is really the same as hand calcs.  and i like this.  i get to select unbraced lengths, k factors, column braced lengths, etc.  it's all pretty neat, in my opinion.
i am now shopping for another fea program, but as much as i want to get a program for analysis and design, i can't bring myself to buy into the "black box" approach.  but i get the feeling i'm doing things the hard way, again.  
-mike
when i first started using our software here (risa 2d and 3d) i would set up several different beams and columns and so on that i could readily solve by hand and check that the software and i came to the same conclusion on allowables and code checks.  you also find out what the software does and doesn't consider by doing this.  for instance, risa does check cold-formed steel members but does not check web crippling.  it does not specifically point this out on your output sheets.  being able to identify and re