Integrated Excel workbook for Wood Structure Design 3

[AELLC]

I have seen many Excel worksheets that do individual design tasks and I wanted to start a discussion regarding integrating all that into one large workbook to streamline the entire design process.

I have my own workbook that I have improved over about 18 years and wanted to share ideas, etc.

It is Excel 2010 but can be saved as 2003-2007 with minor loss of functionality. It has no macros, UDF, or VBA etc., just basic Excel formulas, and nothing iterative.

I don't want to get into VBA discussions because not everyone is familiar with that.

 

[AELLC]

I considered the conc stem wall to be a conc beam to reduce the ecc.

 

[jeffhed]

How much did you consider it reduced it? Does it REMOVE it?

 

[AELLC]

Not completely removed. It was a SWAG approximation anyway. I have to do this stuff all the time. Maybe it is a taboo subject, because no one else seems to complain about it - these gray calculations.

 

[jeffhed]

I would probably agree with that. I have maybe been a little overconservative with my corner footings. I think with everything that is there, a SWAG is about the best we can do. In all actuality, the nailing of the exterior sheathing probably helps transfer the load away from the corner as well.

 

[AELLC]

Same thing about this statement - and do not throw rocks at me - I did not utter this statement originally, I am just repeating it.

"A typical tract house in the USA, in a non-seismic, non-hurricane or non-tornado region does not need lateral design engineering at all. No shear walls, no hold downs. Not even IRC required items. (Except temporary construction phase wind cross-bracing at the 4 basic corners of the house)

All the rooms taken as an assemblage of boxes fitted to each other with wood studs, gypsum wall board and gypsum ceiling board, AND the roof all together, comprise a surprisingly strong structure that will not fail in any way when subjected to normal wind loads."

 

[jeffhed]

We had some flooding a few years back where the river undermined some houses. Some of the houses had 50% of their foundation washed way yet they just hung there. Imagine the engineering involved to make a house hang over the river like that. There would be huge beams and deep foundation elements involved. However, we don't live in a world where engineering judgement can be the rule. Many times on homes we are just trying to show we have done some due diligence, especially where lateral is involved. My goal on everything I do is to be able to have numbers to back up what I do, even if they are not included in the calculation package, I have numbers somewhere to show why I did something.

 

[jayrod12]

Honestly I would agree with that statement. We are in a non-seismic, tornado or hurricane zone and I have yet to run a whole building lateral load analysis for a residential project. Besides designing tall walls and king studs I rarely ever even consider wind.

 

[AELLC]

@ jeff-
yep DUE DILIGENCE - powerful concept.

@ jay -
LOL, I am glad I don't live where you do - being req'd to do lateral calcs is my bread and butter here.

 

[jayrod12]

The only thing that sucks about not having to do lateral calcs is residential design is boring. Even the new large custom builds are the same old-same old.

If you've fought with one contractor to put a steel column in the tall wall full of windows you've fought with them all.

 

[AELLC]

Large custom builds are boring? OMG, not around here.

Residential and ESPECIALLY wood multi-family does burn you out, really badly. That is a huge reason that drove me to integrate my Excel workbook, ta-da.

I have never had to put a steel column in a tall wall. Mostly the outside deck or patio roof saved me.

 

[jeffhed]

I would say large custom builds can be frusterating, not boring. Here seismic also controls and it makes it a major pain to get your lateral forces through your structure and to the foundation. Many of my custom builds here though are high end and require steel columns at the least, if not steel moment frames. I have had about 5 homes in the last 6 months that needed steel moment frames.

 

[AELLC]

If I spec'd a steel m-f, the contractor would kill me.

I have BTDT for large customs in SoCal, very nasty and gruesome processes.

 

[jeffhed]

The contractors I deal with know I won't design a SMF unless I absolutely have to. They trust me and know I have everyone's best interest at heart. Those contractors can be hard to find. BTDT? Can't figure out what that is.

 

[AELLC]

Been There Done That

 

[AELLC]

I have spec'd 5 Simpson Strong-Walls here. (the wood kind)

How many actually gotten built into the structure?

Zero, zip, nada.

 

[jeffhed]

Really? How do they pass inspection when they aren't there?

 

[AELLC]

I had to cobble together a field fix - a lot of busted concrete, scraps of plywood, and hundreds of nails.

I pointed this out to Simpson and we are working on a solution.

 

[AELLC]

I think this thread gets to chasing a of rabbits, but that's OK - back to the last major item, has does anyone have any yeas/nays, or advice, or favorite analysis methods on the subject of analyzing continuous beams and girder trusses quickly and efficiently?

The definition of a structural engineer: overdesign by a factor of 1.999, instead of the usual 2.

 

[jeffhed]

I think the reactions are easy enough, its determining the deflection without plotting a bunch of points to determine the location of the maximum deflection that is the problem for me.

 

[AELLC]

If I had the time, I could "reverse-engineer" the Beamanal spreadsheet to figure out how it calcs deflections.

Right now, I am overloaded with work.

The definition of a structural engineer: overdesign by a factor of 1.999, instead of the usual 2.