Codes too complex!

[sdz]

The constant additional complexity of the codes just adds work with little additional benefit.

When I started work many years ago (all in working stress & imperial measurements) I could keep 4 draftsmen on the go - that's using a slide rule!! Then the codes were A5 size and 10mm thick.

These days I am lucky to keep 1 & 1/2 draftsmen going.

Though the speed of drafting has increased because of CAD, the major reason for the change is the complexity of the codes and the need to check a 40 plus load cases (in Oil & Gas 120 plus) rather than the 3 or 4 you would have gauged to be the worst cases.

When the provisions for shear in slabs in the concrete code changed in about 1990 to be the same as beams (more conservative), I got onto one of the code committee and asked why the change as the American and British codes had not.

His response was that he agreed with me that the change was conservative and unnecessary but it had the advantage that now you only needed one formula to check shear in both beams and slabs!! Now in heavy foundation slabs you have to add shear reinforcement when previously you did not.

However though he did not agree with the change, he had 14 other points he wished to get through the committee so he had to compromise some where!!

So while our code committees comprise academics and representatives of manufactures and are under represented by "working design engineers" we are going to get more complex codes with additional conservatism, resulting in additional costs in construction and design without any true benifit.

The only way most of us understand the Concrete Code on the design of long columns is to buy "Reinforced Concrete" by Warner, Rangan and Hall - what a good way of making sure your book sells.

Some time ago the British Codes allowed you to use either Working Stress or Ultimate State design ( I don't know if this is the case still) - invariable most engineers used the simpler Working Stress. I believe that this choice should be the case here.

A few years ago the Institute of Structural Engineers in London did some checks of existing buildings using the Ultimate Stress method and found that they did not past muster. The buildings had been built only a few years earlier - designed using working stress. This caused a dilemma - which approach is right or is it just that one method is more conservative?

The only failures of "engineered structures" I have come across have been either due to poor detailing (stiffeners left out of bin ring girder at support point), lack of adequate maintenance (corrosion causing failure), increases in mechanical loads without a structural check, operator error, material fatigue/imperfection (in a stacker/reclaimer shaft) or ground movement. This is for structures built in the 60's to the present day.

Hope this give you food for thought as to how our code committees work and also gives vent to my cynicism

(reproduced with permission of author)

 

[hokie66]

A similar thread on the "Structural Engineering Other Topics" forum for the last three days got so heated I think the editors have censored it. Sounds like the US codes are even worse than ours.

 

[BarryEng]

I have been on several code committees & on one occasion, I tried to change some fundamental thinking. I wanted a 'two or three tier' design for some parameters. For example, if you want to design one slab for deflection, you can use (for example on a cantilever slab) an L/D of 12. If you have 10 slabs, you can use the cracked I & Z & do a deflection calc. If you have a multistory building & you have 100 slabs, you can use a more sophisticated method of analysis using tension stiffening between cracks etc etc.

I was constantly told by the other members of the committee (a good proportion of academics) that EVERYONE has a computer on their desks with ALL code provisions as a series of spreadsheets & so a sophisticated method of analysis is OK. My argument was that if an engineering firm (with only one engineer working from home) wanted to design a column between two garage doors to support an elevated slab, he only required a very simplified (but conservative) method of design - for a "one off" design.

I wanted a "low level" design provisions (consevative) for a "one off" design & a "better" (more accurate but less conservative) design for a large number of items. The design level being based on "what does it matter if the design is slightly conservative on a one off design".

I lost that argument.

I have seen codes become thicker & thicker over the years. This is proably OK for "wrinklies" (engineers of mature years that have been in the game a long time) who will gradually adapt to changing requirements, but I am concerned about younger engineers that have a VERY steep learning curve to design, even a VERY simple beam or column.

 

[stanier]

I sit on three code committees. They are dominated by manufacturers and water authoriites. Very few working engineers.

Manufacturers use the standards as marketting tools. They try to nobble the oppostion. Also it is a great way to be able to hide behind the defence of a failed product by saying "it complies with AS/ANZ XXXX" Even though your company was instrumental in getting the standard up in the first place.

Some manufacturers' representatives hold the view that if they can produce it, it should have a standard. That to me is completely wrong. It just means you can make rubbish consistently. "Standard" doesnt mean "high standard" in their eyes.

There is always good old fortress Australia where the codes keep out the overseas products and services.

It is hard for the government instrumentalities to get anywhere and the funds to send people appear to be dwindling.

Geoffrey D Stone FIMechE C.Eng;FIEAust CP Eng

http://www.waterhammer.bigblog.com.au

 

[gr2vessels]

Politics. Australia is now fully dependent on many foreign standards, due to a weak government unable to go past some peculiar selfish interests, benefiting the well known "nepotism" thought to be inheritet only by the communist countries. Money talks and ....walks. However, one day someone will shout, enough is enough. Today, a new government might bring some hope...Until then, yours
gr2vessels

 

[hokie66]

gr2,

I think you give government too much credit. The politicians wouldn't know anything about the codes we have to deal with every day. We can only blame ourselves and our professional associations for apathy in allowing this sorry state of affairs.

 

[OzEng80]

BarryEng I like your idea - it's a shame you couldn't get it through. It seems appropriate that the importance of an element should be relative to the design time required.

I suppose if it did go through we could have gotten overrun with building designers taking our jobs and builders questioning member sizes with some actual design scrathings to back it up!

 

[BarryEng]

To Stanier
Yes I worked for a water authority BUT on a code committee, I represented the utility & not Australia. I was criticised for insisting on a set of OD's for PVC pipe that were developed in Oz from DI pipe & hence prevented overseas manufacurers from selling their products in Oz. I did this, because I represented the utility & hence the best result (for the utility) was to have a set of fittings (bends, tees, tapping bands, repair clamps etc etc) that would fit on ONE OD pipe (such as CI, DI, AC, steel, PVC). This meant that maintenance trucks only needed one set of pipe OD fittings.

To change an AS to match on overseas std, EVERY water utility in Oz would have to bite the bullet & keep two sets of fittings on trucks (& in the stores) forever.

Eventually, this will happen & every truck will require to stock two sets of repair materials (& conversion pieces for every pipe material).

What overseas std should we use? ISO? My experience is that ISO includes EVERY factory that produces pipe in Europe (is 'international standards organisation' correct or should it be European stds?). Just have a look at the ISO list for PE pipe for confirmation.

While I am on my hobby horse - no one has yet explained to me why PVC has a FOS of 2.15 (50 year) & PE has a FOS of 1.25.

In the second para above, I said that eventually the utilities would have to change (& they will). At present we have (in Oz) AWA who try to become the 'peak body' for utilities. They are based on the east coast & predominantly have Sydney or Melb experience & based on being located about one or two HOURS driving from their head office. I was based a min of two or three full DAYS driving from the limit of my responsibility. What would they know of problems of distance problems for utility operations? Do they EVER derate PVC or PE pipe for temperature? Of course not - so how can the 'peak body' effectively represent ALL utilities & their problems?

To hokie66
If the 'peak body' represents ALL water utilites, almost all utilites will not send representatives to committees (why should we send someone 3,500 km to a committee meeting when we have a 'local' who will represent us). This is a defacto political control because the utility 'bean counters' can save money by not being represented on committees. As I said in the para above, what would someone in Melb know about 40 deg water temp effects on pipe?

As Stanier said - "I sit on three code committees. They are dominated by manufacturers and water authoriites. Very few working engineers." I agree. The problem is that utilties (in the past) could absorb the cost of committee representation. Manufacturers HAVE to be there to ensure that their agenda is satisfied. Manufacturers always had an 'industry' meeting on the day before the committee meeting. This ensured that they had a united front (or agreed argument) already discussed. I tried on several occasions to do this with utilites but the 'bean counters' put the nobblers on that suggestion.

Another problem is that only 'working engineers' from Sydney or Melb can become members of a committee (because of the cost of the exercise). I tried for years to have AT LEAST ONE meeting (& I have been on many committees) on the west coast but I never convinced anyone (on the east coast). It was OK for me to travel 3,500 km to every committee meeting, but there was ALWAYS a good reason why they could not meet elsewhere.

 

[csd72]

There are things you can do to get involved as a working engineer.

The first drafts of new standards are usually circulated for comment. I do know of some working engineers that are on code commitees also.

 

[stanier]

Barry Eng,

I think we are in violent agreement on a number of issues.

Now standards are holding meetings all over the place. The manufacturers have cottoned onto the fact that utilities cannot afford to send people all over the place. The next meeting is in Auckland. Imagine someone from Kalgoolie getting permission for overseas travel.

By having meetings at different venues there is a disconnect by the WSAA and utility represntatives so that the manufacturing oligarchy dominates.

The committees are slow to adopt modern techniques such as teleconferencing.

csd72,
Written submissions on drafts are largely ignored. In fact decisions at one meeting are overturned at the next meeting if strong opinions from the manufacturing cadres are want to.

 

[BarryEng]

To stanier,

It looks as if we are both preaching to the converted.

I agree with your comment (not again!!!) about written submissions to a draft. I have been in many situations where the arguments are more cohesive (& convincing) when delivered by a rep from a manufacturer on the day. It is VERY difficult to argue your case (from a written submission) when you do not even have the chance of a rebuttal of evidence or are given the chance to qualify any points that you make. The chairman must make a decision on the day or wait for the next meeting - in most cases, a vote on the day carries the most weight.

Remember that most manufacturers have a meeting usually on the day before & they air their 'dirty linen' only in their own company. They come to a consensus (not necessarily an agreement) & put up a united front to the committee.

Divide & conquer.

I do not condemn this action at all - in fact I agree with it. I just wish that the utilities (read 'bean counters') came to the same conclusion as to the future effect on costs to the utilites (forever) on the consequences of the decisions made at committees.

The problem is - everyone agrees that planning & design can save a LOT MORE money than you can ever save in construction & operation. But this is never reflected in (for example) salaries & working conditions. Design looks after about 7 to 8 % of the project cost, but construction looks after over 90 %.

Taking a logical step further back in time, setting standards (that can have adverse effects when the implications are not well thought out), can have repercusions for many years. For example, changing the PE OD's to ISO values. The variation of fittings (& pipe OD's) would be enormous. Standards are not to allow an Oz manufacturer get rich, they are to establish a set of MINIMUM guidelines. Eventually, we will get world wide codes - but not yet.

Another example - have a look at the allowable stress for pressure vessels. Min stress is 1.0 times allowable. Combinations will allow an increase to 1.5 allowable & eventually 3 times allowable. The ASME code has the same chart as the USBR power penstocks, & this is the same as in AS 1210 (supp). This 'world wide' trend will eventually increase to the extent that (in Oz) AWA will be the rep for the utilities, & some other body will take over the role for the world. ISO have tried but the Europeans, Brits & USA cannot agree - but it will come.

 

[csd72]

This is another thing that the government has essentially privatised and shouldnt have.

A government body, though innefficient, is at least capable of making unbiased decisions on these things.

The manufacturers should be given a comment on this, but should never be part of the decision making process. The term 'conflict of interest' comes to mind.

 

[stanier]

csd72,

I tried to have representatives of manufacturers excluded from voting when there was a conflict of interests. This was thwarted by the "PIPA mafia" as they do not represent individual companies but trade organizations.

They will always argue their role is to represent their company's interests.

"Sales are about honesty, integrity and ethics. When you are able to fake these you will be successful" .
From a defrocked sales director

BarryEng,

You are right about the meetings prior to Standards meetings. I actually overheard an argument between PACIA (now PIPA) members at a conference on the eve of a meeting. As you say consensus was reached because the big boys held sway over the minnows.