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Foundation Best Practice - And Adding Rebar?


Linicks

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All,

I have drawn my foundation and footings on separate layers customizing the footing as a short and wide wall. Is this the best practice in VW2010?

Additionally, I would like to add rebar to the stem walls and footings. I'm not sure how to model a solid round steel rod that I can insert into the footings and walls. Any help would be appreciated. Ultimately, I would like to be able to take a cross section for foundation for construction details, and quantify the volume of concrete and rebar for estimating purposes.

Thanks!

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An Architect who draws reinforcements is a fool. Surely in most countries one has to have a certified engineer to do computations and to determine the reinforcements?

That includes other things in addition to the bars. Miraculously, reinforced concrete structures have been built for 150 years without modeling rebars. Daresay, the blokes on the site are quite capable of interpreting and adapting fairly schematic, old fashioned drawings.

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No, it is not. Unless the Architect is also a Certified Structural Engineer and does all the computations etc. in the project, he or she should NOT show such things in his or her drawings, otherwise he or she may become responsible for them.

EDIT

Or, even worse, responsible for discrepancies between his or her drawings and the Engineer's drawings: a situation which buys the Contractor a new Porsche.

Edited by Kool Aid
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An Architect who draws reinforcements is a fool. Surely in most countries one has to have a certified engineer to do computations and to determine the reinforcements?

That includes other things in addition to the bars. Miraculously, reinforced concrete structures have been built for 150 years without modeling rebars. Daresay, the blokes on the site are quite capable of interpreting and adapting fairly schematic, old fashioned drawings.

Well, in my case I want/need to model construction details like rebar placement because I'm the "Bloke" on site actually doing the work. Yes, I know it's hard to believe that there are people out there that actually build what they design. By the way, in my region, all a builder has to do is meet the minimum building codes. Unfortunately, these requirements are very minimal, so I typically add much more rebar than is required for residential construction. I go the extra mile here because there is no more important component of a structure than it's foundation. If you are in a position where you are concerned about the integrity of the concrete and its reinforcement, you probably aught to have a structural engineer review it anyway. Of course thats only after you have you have done your soils tests. I can also say from experience that concrete contractors hate getting foundation plans that are minimalistic. It wastes there time and energy trying to deal vague plans which costs them money. Additionally, they don't want Porches, give them a new diesel pickup and they'll be happy :)

In summary, modeling these details allows me to achieve the following goals:

- Analysis: I can accurately estimate the quantity of materials needed for the job, and resolve design issues before getting to the field. It costs allot more to do this in the field.

- Communication: If I need to hand the project over to an employee or sub-contractor, I can hand them a detailed drawing of the rebar grid, etc. This makes it easier for them to get it right the first time, and saves allot of time, money, and frustration.

The bottom line is that different people have different needs, and I'm trying to utilize tools like VW to achieve mine.

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Wonderful, admirable, fascinating!

OK. We have a scale issue here: I've never designed a house, so I have no idea of the requirements. The engineers' drawings of beams, columns, slabs, foundations etc. I've dealt with have been remarkably detailed and largely beyond my comprehension, especially as comes to pre-stressed elements.

I couldn't build even a dog house?

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Important point here: He's not discussing pre-stress, pre-form concrete for industrial/commercial applications. He's referring to a poured residential foundation with rebar. US residential codes are pretty lax, and they are local, when it refers to residential construction. No engineer required usually, so long as you follow the minimum best practices and codes for your city/county.

I agree with Peter that Duplicate Along Path is a fine way, once you've for a base shape for rebar. Or Extrude along Path if you're not that worried about the texture of the rebar.

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By the way, in my region, all a builder has to do is meet the minimum building codes. Unfortunately, these requirements are very minimal, so I typically add much more rebar than is required for residential construction.

Well intentioned, but not a good idea.

Over reinforced concrete is subject to sudden catastrophic failure.

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By the way, in my region, all a builder has to do is meet the minimum building codes. Unfortunately, these requirements are very minimal, so I typically add much more rebar than is required for residential construction.

Well intentioned, but not a good idea.

Over reinforced concrete is subject to sudden catastrophic failure.

I'm sure that over reinforcement is possible, but I have never seen it in the construction projects that I've been associated with. It does get old tying all that re-bar together though :). For residential construction in my area, minimum code says that you only need two (one on top, one on the bottom) horizontal rows of #4 re-bar within 12" of the top and bottom of an 8" x 8' wall, and vertical #4's every four feet. In a typical 8" x 16" footing two parallel rows of #4 re-bar is required. I typically double this by placing the re-bar in a 24" grid pattern. Still very minimal when you consider how much re-bar can be added before seeing negative effects. I also use 3500 or greater psi concrete instead of the minimum 3000. I have seen failures when foundations are built to the minimums, and haven't had any failures in the foundations built using the method that I prefer.

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Important point here: He's not discussing pre-stress, pre-form concrete for industrial/commercial applications. He's referring to a poured residential foundation with rebar. US residential codes are pretty lax, and they are local, when it refers to residential construction. No engineer required usually, so long as you follow the minimum best practices and codes for your city/county.

I agree with Peter that Duplicate Along Path is a fine way, once you've for a base shape for rebar. Or Extrude along Path if you're not that worried about the texture of the rebar.

I tried the extrude along path method, but would like a better solution. I will try the Duplicate Along Path method when I get a chance. It seems like the foundation components should have been added to the wall object a long time ago. It's all pretty standard, and all of my projects will have some kind of foundation. Hopefully, this will added this soon.

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How about improved tools for every user,LOL....Duplicate along a path each bar, thats their simplistic solution for everything in this program.The guy who wrote that code must be laughing all the way to the bank. I requested years ago the ability to extrude Std (engineering) details,has that been implimented? They should have a good look at revit reo tool and try benchmark comparisons.Whats needed is a basic tool for concrete slabs/walls/beams/columns, enough with the ArtyFarty noodle rendering styles.HTH

It seems silly that they haven't added this functionality already. It's not a technical hurdle because all the needed code is there, they just haven't added it. Hopefully, it will come sooner rather than later. When is the last time to you saw a structure without a foundation. With the exceptions of bars and sheds there aren't many.

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Can I tell you how many times I get a stupid contractor asking stupid questions like, "can I leave out the rebar", or, "I didn't know rebar was required".

A lot of contractors don't own a copy of the Residential Code of New York State (based on International Code). So if I don't put a detailed rebar specification into the foundation wall note for that unbalanced structural basement wall, then the rebar won't get put in. The code has a prescriptive chart, showing height of ceiling in the basement, compared to the height of the grade outside the wall, which all determine EXACT rebar sizes, amounts, and spacing. It's not designed by some other engineer. How pathetic have we become that we need engineers to hold our hands for everything. Have architects been degraded to mere "designers of interesting curves and fanciful dreams"?

And if the cheesy cheepo architect/draftsman decides to just put "rebar to code" or "as required" then you'd BETTER be available day and night for stupid project bidding questions.

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BTW, if I was to model the rebar I'd make it square to save on rendering time.

Even so, modeling every rebar is pointless. Even in a modest 10000 m2 5-storey building there are tons of reinforcement.

A section, a type; for beams and columns maybe a plan and an elevation, but typically the same beam or column is used tens of times.

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Oh, so do I! I can easily imagine a situation in which eg. Tekla Structures helps the structural engineer to determine the reinforcement of structures of an olympic Vvenue, an opera house or a bridge.

Suburban architects designing houses without engineers? Suburban engineers doing Computations for carport extensions? Ah, well!

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MACmansion

I'm assuming that you are referring to the non de-script all square footage, cookie cutter homes that you find in many sub-divisions in the US. I agree that they are often ugly and boring, but are a fact of life in the US. Interestingly, I meet a builder that was visiting from Europe that was tired of building with stone, and wanted to learn how to duplicate those building practices. Also, don't you mean McMansion?

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Linicks, this is what you do.

do the footings w/ wall tool like you have done.

do the wall like you have done.

do rebar on separate layer, extrude along path etc

then do a section vp of the footing and wall.

then do another section vp over the top of the 1st and have only the rebar layer on.

what you cannot do is get the length of all your rebar. it is on the wish list.

(see "piping tool")

i attached a pick to show what can be done. but cannot get info to spread sheet.

as for some of you, people should not have to justify themselves as to why they want to do something. once again a simple request does not get answered.

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