Discussion: View Thread

Unit of calculation

  • 1.  Unit of calculation

    Posted 03-01-2018 10:08 AM
    Edited by Tirza Austin 03-01-2018 10:08 AM
    Why does the USA and other countries use FPS units for calculation, when the originator of FPS units
    (the UK) has shifted to the MKS system?

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    Partha Aich M.ASCE
    Director
    Delhi East ND
    ------------------------------


  • 2.  RE: Unit of calculation

    Posted 03-02-2018 11:54 AM
    Good question, but it may be answered by practicing engineers in the UK!
    Personally I think it depends on ease of usage and also the manufacturers, which unit they follow in production of building materials and maintain specifications.

    ------------------------------
    Peter Singh M.ASCE
    Managing Director
    Kingdom Designers
    Birganj
    ------------------------------



  • 3.  RE: Unit of calculation

    Posted 03-02-2018 12:01 PM
    Edited by Chad Morrison 03-02-2018 01:15 PM
    FPS system is useful in construction.  Working in units of 12 makes it easy to divide by 2 or 3.  There is also the issue of field tolerance.  In general a difference of 1/8" or less can be neglected and accommodated in the field fit up.  Measuring in any unit less (mm) is not significant to the overall design.  When an ironworker is welding, it is easy for him to measure to the nearest 1/16" of an inch rather than to the nearest mm which is not significant. As the engineer, we are very interested in making the units work in our formulas, but the information is not valuable unless the worker can read, measure, and construct the project quickly without error.

    Measuring force and weight in units of pounds is also useful in construction.  Everything we build (unless it is underwater or in outer space) is subjected to the force of gravity.  So, the weight of a 15,000 lbs beam can be used to calculations for force, stress, and any other desired calculations and the crane operator can also determine if he can lift it.  So while pounds are not technically a unit of mass, no conversion between Newtons and Kilograms needs to be made at any point in the process.  All work that I do, from the shop drawings to the crane  pick and the calculations I perform in between deals in terms of pounds.  There is no chance for confusion between Newtons and Kilograms to occur.

    In many scientific and engineering fields MKS units are very effective and preferable.  In construction, they are not.  I do not want to use the reason "it has always been done that way," but in cases where we are renovating existing buildings, the existing member sizes and drawings are in FPS.  So, mixing of units would be troublesome.

    ------------------------------
    Chad Morrison P.E., M.ASCE
    Professional Engineer
    Greenville RI
    ------------------------------



  • 4.  RE: Unit of calculation

    Posted 03-03-2018 04:02 PM
    ​Chad- As a semi-retired Rigging (Heavy Lift) Engineer, I appreciate anyone who gives accurate weights to crane operators- as overloading is one of the largest causes of crane accidents. Crane operators will frequently encounter confusing terms within the load charts and operator's manuals when operating European or Asian cranes. When confronted with a term like "kilonewtons per meter squared", the normal action is to quickly turn the page and go about their business.

    An area that should be discussed is 'decimalization'. Many vendors and suppliers from other countries think that we don't use decimalization at all and rely on fractions throughout. (I recall my early days in the 1960's having to immediately convert in my head (for the carpenters) the information from the design drawings as well as my readings from my level).

    Some European and Asian vendors make an honest attempt to supply information in both metric and English units- some with confusing results such as "10.6 13/16 inches". When using data from a vendor's equipment drawing, I find that it is easier to do everything in the given metric units and convert only in the end.



    ------------------------------
    James Worrell
    Mostly Retired
    PE, RLS (retired)
    Raleigh NC
    [jimworrell@...]
    ------------------------------



  • 5.  RE: Unit of calculation

    Posted 03-05-2018 09:58 AM
    There was significant pushback from the Construction industry as has already been mentioned, as well as a vast level of existing infrastructure which was built using feet and inches, making things difficult match when using metric.  Land titles and survey information...state plane coordinate systems...the existing framework that infrastructure is built around was all done in English units, but what it really came down to, I believe, is money.  Many public agencies saw costs rise in engineering due to either dual-dimensioning or re-work due to the "hard vs. soft" conversion confusion (do you replace an existing 10-foot shoulder with a 3-meter shoulder, or a 3.048-meter shoulder?). There was also an increase in RFI's during construction for plan interpretation as well as a difficulty in finding construction inspectors that could function well with mixed dimensions.  The attempt to go metric had gone on long enough that switching BACK to English units was seen as a cost-saving measure by some public agencies.

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    Kensey Russell P.E., M.ASCE
    HNTB
    Oklahoma City OK
    ------------------------------



  • 6.  RE: Unit of calculation

    Posted 03-05-2018 02:52 PM
    Edited by Tirza Austin 03-05-2018 02:51 PM

    Amen to this

    I have been deeply involved in construction and engineering since 1953.  I have been involved in all the ins and outs of working with construction and conveying understandable drawing, specs and other information.  There are enough problems with what is known let alone what we think. We can better improve the engineering to construction relationship staying with the system that is still well known.   Engineering may work well with the Metric system but the FPS is too ingrained in general construction.  There may be the money and mechanics available in mega projects to train the work force in the Metric system but other than that my opinion after 60 years + is it is not broken, lets not try and fix it!   The good results speak for themselves.  

    I believe that all the attempts of trying to force the metric system on engineering's relationship to providing good workable field information has demonstrated that the tried and proven ways (FPS) is still the way to go.  Let the other countries do what they want.  Let’s not reinvent the wheel in the USA!!!!



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    Allen Hulshizer P.E., F.ASCE
    Consulting Structural Engineer
    Chalfont PA
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  • 7.  RE: Unit of calculation

    Posted 03-02-2018 12:09 PM
    Edited by Tirza Austin 03-02-2018 12:08 PM
    Legacy.
    They tried, at least partially in the early 2000s and my understanding is that the pushback was so big this effort was abandoned. You can find some DOT codes and projects from the late 1990s, early 2000s in MKS for reference. I believe AASHTO Bridge still comes out in MKS, probably to help when used as design code in other countries - the middle east comes to mind.


    ------------------------------
    Nikola Nikolov
    Structural Engineer

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  • 8.  RE: Unit of calculation

    Posted 03-03-2018 04:00 PM

    Oh my!  I lived through that; changing completed plans, rewriting specifications, converting standards.  Let's not do that again!

     

    As I recall, the pipe manufactures were one of the key opponents to repeal the change because of the high cost of converting their manufacturing facilities.

     

     






  • 9.  RE: Unit of calculation

    Posted 03-03-2018 04:06 PM
      |   view attached

    USA and 6 other small developing countries are the only ones that still use the old British system. However the SI (System International) is the recommended unit of measure by the US Federal Government - and many disciplines including science, medicine, defense and some commercial products already use the SI system. Since the adoption of SI is voluntary (unlike many other countries where it was made mandatory), many activities including engineering practice, journalism and weather forecasting have yet to act on it – instead use both the systems – sometimes confusing things.

    Have a look at the attached NIST document to know more.



    ------------------------------
    Dr. Dilip Barua, Ph.D, P.Eng, M. ASCE
    Vancouver, BC, Canada
    Website: https://widecanvas.weebly.com
    ------------------------------

    Attachment(s)

    pdf
    NIST - US SI system.pdf   1.29 MB 1 version


  • 10.  RE: Unit of calculation

    Posted 03-05-2018 09:55 AM
    ​Perhaps this NIST document is more helpful for engineers:

    https://www.nist.gov/sites/default/files/documents/pml/wmd/metric/SP1038.pdf

    ------------------------------
    John Helmers P.E., M.ASCE
    Director of Environmental Resources
    Olmsted County Public Works
    Stewartville MN
    ------------------------------



  • 11.  RE: Unit of calculation

    Posted 04-13-2018 04:10 PM
    Edited by Tirza Austin 04-13-2018 04:10 PM

    The continuation of this debate (Martin Mungwa initiated this round) in the Collaborate ASCE forum suggests the importance of this topic. John Helmers citation of the NIST Presidential Measurement Timeline shows that various presidents – from George Washington (1790) to Bill Clinton (1993) – US Federal Government was very keen to implement a uniform system of measurements – the SI system. The problem is that US governing system has a very high devolution of powers from Federal to State to Counties – making things mandatory very difficult. But where there is a strong will, there is a way.

    The birthplace of the imperial system – the United Kingdom switched to the SI system in 1995 declaring it mandatory. In part this was necessary to integrate itself to the EEC (European Economic Community) countries. Once, one of my British colleagues lamented that Britain took this unfortunate step while the USA was still following the imperial system. Some would certainly feel disappointments when things change.

    I remember how a small country like Bangladesh switched to the SI system in 1982. After government approval, Bangladesh Standards Organization started a years-long campaign through advertisements and pamphlets including the use of NGOs going to people and businesses – convincing people the benefits of switching to the SI system. The organization issued measuring weights, tapes etc. before the mandatory deadline taking the effect. Interestingly many businesses started switching to the new system before the deadline.

    It is just human nature that we feel reluctant to go beyond our comfort zone. But when it comes down to avoiding confusion and ensuring public safety – it is necessary that everybody comes together.  



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    Dr. Dilip Barua, Ph.D, P.Eng, M. ASCE
    Vancouver, BC, Canada
    Website: https://widecanvas.weebly.com
    ------------------------------



  • 12.  RE: Unit of calculation

    Posted 04-27-2018 11:06 AM
    Edited by Tirza Austin 04-27-2018 11:05 AM
    Engineers need to be well versed in both methods.  If involved in an dynamic calculations you quickly find merits to the SI system.  Advent of computer digital documents may allow for easy conversion of measurements to the SI system when viewing documents.  Engineers may not be the driver but we need to be versatile in the world market.

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    Alan Johnson [P.E. M. ASCE
    [Consulting Engineer
    Fraser MI
    ------------------------------



  • 13.  RE: Unit of calculation

    Posted 04-09-2018 08:53 AM
    Edited by Tirza Austin 04-09-2018 08:52 AM
    ​The key word here is mandatory. As long as it is not mandatory to use the metric system it will be a hard sale for American engineers to fully convert and join the rest of the world. A complete and global conversion to SI or metric system will certainly pave the way to unifying engineers and engineering practice worldwide.

    ------------------------------
    Martin Mungwa P.E., M.ASCE
    Engineering Manager
    Consolidated Edison Company of New York
    New York NY
    ------------------------------



  • 14.  RE: Unit of calculation

    Posted 04-10-2018 05:44 PM
    Yes, the key word *is* mandatory. I grew up in the 1960s and 70s and I remember when I was in elementary school when the metric system was introduced. There was talk of making SI mandatory for a while, but the federal government never followed through on it. Hence, here in the States the engineering profession still does the majority of its work in US English units and if I'm not mistaken, all of the calculations. In which case the metric units are only presented on the project plans as an alternative.





  • 15.  RE: Unit of calculation

    Posted 04-11-2018 11:38 AM
    Edited by Tirza Austin 04-11-2018 11:38 AM
    While it hasn't stuck, there certainly have been "pushes" at the federal level over the years.  One of the first projects I was involved with was an IRS facility in Chamblee, GA.  We initially did the design in Imperial units per standard practice.  We were later asked to convert all the dimensions and measured call outs to SI.  Naturally this isn't a straight conversion, given that items are typically expressed in nominal units (e.g., 24-inch curb & gutter becomes 600mm c&g rather than 609.6mm), and they wanted the line work to match.

    Ironically (or maybe predictably), the awarded contractor was used to working in Imperial rather than SI, so they endued up paying us to convert everything back.  Bureaucracy; enough said.

    ------------------------------
    Eric Pilcher P.E.

    ------------------------------



  • 16.  RE: Unit of calculation

    Posted 04-12-2018 10:50 AM
    As I recall, there was a federal law mandating the move to SI. That movement ended when the states, counties and municipal governments demanded the federal government pay to change all the speed limit, mile marker, distance-related, bridge clearance, and bridge weight limit signs to SI.

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    Bruce Podwal P.E., F.ASCE
    New York City NY
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  • 17.  RE: Unit of calculation

    Posted 04-13-2018 10:54 AM
    Edited by Tirza Austin 04-13-2018 10:53 AM

    The metric system makes sense and it's definitely easier to calculate, but it will likely never catch on in the US; at least for projects in the US. To me the root of the problem is people born and raised in the US have learned to "visualize" SI units: 

    * When I hear something is 2 feet long or weights 30 lbs or concrete has Fc' of 3500 psi or is 3 miles away, I can instantly visualize what that represents.

    * But, when I hear something is X cm long, weights Y kg or concrete is Z mega-pascal, I have to do a converstion, either in my head or on paper.  Heck, I've been a civil engineer for 33 years and I still can't remember if a kg weight is more than a pound or a kilometer is longer than a mile.

    This is like growing up learning a language and then trying to learn a second language as an adult. Difficult.

    On  a side note, TXDOT produced a metric spec book about 25 years ago and design/let a few test jobs using those units  As I recall, they did not go well. The designers had several errors related to having to the use of metric units and the contractors have both estimating errors and field lay-out/construction errors. The whole concept went away quite quickly.  BD



    ------------------------------
    Bryan Danielsen P.E., M.ASCE
    Director of Business Development - Construction Services
    Lamb-Star Engineering
    Plano TX
    ------------------------------



  • 18.  RE: Unit of calculation

    Posted 03-05-2018 11:03 AM
    Edited by Tirza Austin 03-05-2018 11:03 AM
    The US economy was large enough to allow the push back for the British (imperial) measurement  system to be retained.  For Countries exporting construction material to the US imperial sizes are still maintained.  Example wood construction.
    However if you check manufacturing you will find machine bolts are done in metric sizes where the international market dictates it.

    If you check you will find that there are several versions of the metric system.  The SI system that everyone is moving to originated in France.

    Canada moved to the metric system in 1970s  and it stuck.  Canada depends on exports too much to used a different system than the majority of the world.  To put this in perspective  Canada has roughly the same population as California. When I read USW Texts it reminds me of the 1970s when Canada was switching to metric.

    ------------------------------
    David Thompson P.E., M.ASCE
    Principal
    KTA Structural Engineers Ltd.
    Calgary AB
    ------------------------------



  • 19.  RE: Unit of calculation

    Posted 03-06-2018 09:52 AM
    When South Africa withdrew from the British Commonwealth in 1961 it also got rid of the Imperial units and enforced the SI units. The move was done across the board, so that people do not count calories but kJ and watch their mass, not weight. 
    The trouble with the US is that it's economy is more than 100 times larger than South Africa economy was then, so the move is not so easy. With the isolationist winds blowing in Washington the task seems insurmountable.

    ------------------------------
    Joram Amir Ph.D. CE D.GE. F.ASCE
    Piletest.com Ltd.
    Israel
    ------------------------------



  • 20.  RE: Unit of calculation

    Posted 04-10-2018 12:43 PM
    Edited by Tirza Austin 04-10-2018 12:43 PM
    ​I'm curious about the "several versions of the metric system" comment.  Could you expand on this please?  

    Thanks.

    ------------------------------
    Duane Strayer P.E., P.Eng, M.ASCE
    Division Manager, Infrastructure
    Calgary AB
    ------------------------------



  • 21.  RE: Unit of calculation

    Posted 04-11-2018 10:47 AM

    I remember doing a lot of course work in both Imperial and Metric (SI) units during college in the late 1980's because the US was on the verge of making that conversion mandatory, supposedly.  Although that was 30 years ago, as I recall the Metric units were considerably easier to use for engineering calculations so it always puzzled me why the engineering community wasn't more supportive of the conversion to Metric.  Perhaps as a college student I wasn't fully aware of the engineering community's efforts.

     

    At that time the Metric system seemed to be something very new to a large portion of the general US population.  Since then I think the general US population has gained more exposure to it and arguably is more accepting, or at least tolerable of it.  Are there any renewed efforts to make a conversion to the Metric system mandatory?  As with any change those opposing it talk about the cost of making such a conversion.  Has the counter argument regarding the cost of not converting also been presented?

     

    Alan Stuemke, P.E.

    Engineering Manager

    Consolidated Utility District

    Murfreesboro, TN

     






  • 22.  RE: Unit of calculation

    Posted 04-12-2018 12:49 PM
    I was curious about it too. But within a couple of minutes found the following. Metric System - MDARC

    Don't know if it is a particularly reputable source, but the concern about "several versions" seems taken out of context. It has been updated and amended "as science and technology advances," which makes sense.

    "The first metric system was introduced in France in 1799. It has evolved and several versions were introduced over the years until 1960, when the General Conference on Weights and Measures (CGPM) published today's version and called it the International System of Units (SI). The SI has continued to be refined and revised since then, including the definition of a new base unit, the mole; definitions of additional derived units; the redefinition of several units and other refinements. The SI will further evolve in the future, as technology and science advances; allowing, for example, the units of kilogram, ampere, kelvin and mole to be redefined in terms of constants."

    Hope this fuels the debate.

    ------------------------------
    Michael Britton P.E., M.ASCE
    San Luis Obispo CA
    ------------------------------



  • 23.  RE: Unit of calculation

    Posted 03-08-2018 10:31 AM
    I went through all the comments on my question. There were many explanations. Some have even mentioned about high cost involved for conversion in the construction industry, as all equipment has to be re-calibrated. As far as the USA is concerned, cost should not be a criteria.
    In India I studied engineering in FPS system, and that time transition was going on. By the time I passed out of engineering, we were quite conversant with MKS system. India was not that rich at that time. But the conversion was carried out gradually. For example broad gauge railway line was taught to us as 5'6". The converted figure of 1676 mm was also taught. Now we have equipment which manufactures Broad Gauge rails as 1676 mm, meter gauge rails as 1000 mm, narrow gauge as 760 mm etc. Even the rail dimensions have been converted to MKS system from earlier FPS system. We do not have any fuel station which measures in gallons. This conversion started way back in 70's. If calibration at that level was done way back in 70's in India, it could have been done in the US also. Rather we were facing difficulty in going through the earlier editions of AASHTO Codes which were in FPS unit. I think FPS unit is also used in Canada. But in Australia and the UK they have shifted to MKS system. At least in seminars they always refer to the MKS system, which most understand.

    So the question still remains open-ended.

    ------------------------------
    Partha Aich M.ASCE
    Director
    Delhi East ND
    ------------------------------



  • 24.  RE: Unit of calculation

    Posted 03-08-2018 11:21 AM
    Lincoln Chafee's presidential platform? Adopt the metric system, of course.
    Washington Post remove preview
    Lincoln Chafee's presidential platform? Adopt the metric system, of course.
    Well, this is a new one. While announcing his candidacy for the highest office in the land, newly minted Democratic presidential candidate and former Rhode Island senator and governor Lincoln Chafee made the bold case for ... the U.S. to switch to the metric system?
    View this on Washington Post >


    Here is the closest thing to a final answer.  Americans did not take this presidential candidate seriously because of his platform.  That said, the American government does not control the unit system of private industry.  They would only be able to dictate what is used in government contracts.



    ------------------------------
    Chad Morrison P.E., M.ASCE
    Professional Engineer
    Greenville RI
    ------------------------------



  • 25.  RE: Unit of calculation

    Posted 03-09-2018 11:49 AM

    While studying engineering in the late 1960's our professors told us to get used to the SI system of measurement since it was expected to be the standard of measurement in the U.S within the next ten years.  Much of the resistance to the SI system at that time, as I remember it, came from the automobile industry and mechanics working in that field.  Car manufacturers would have to rework their manufacturing processes and mechanics would have to replace their already expensive set of tools with a completely new set in different sizes.  Over the next fifty years however, the influx of foreign automobiles with parts manufactured in SI units has required mechanics to own both sets of tools and, replacement parts are commonly found in that standard.

    Current contract bidding documents for construction are typically issued in the U.S. Customary System and construction trades people will default to the USCS measurements.  An extra degree of confusion and possible error is introduced when shop drawings for products manufactured outside the U.S. come with SI unit measurements.  Many times I've found carpenters, millwrights and plumbers measuring out foundation pads, anchor bolts and pipe sleeves in inches for dimensions found on a shop drawing prepared in SI units.  The only way the SI system will become a standard for construction in the U.S. will be by requiring it to be used in contract documents and by issuing contract documents in that system.



    ------------------------------
    Stanley Bujalski P.E., M.ASCE
    Retired
    Campton NH
    ------------------------------



  • 26.  RE: Unit of calculation

    Posted 03-09-2018 05:42 PM
    I think the last president of the USA who pushed for USA's conversion to SI was Jimmy Carter, a nuclear engineer.  

    At least one very major space catastrophe occurred because of our continued use of English units.  About 10-15 years ago a Mars Lander crashed into Mars, instead of landing peacefully, as a result of the failure to convert the rate of speed units between the international design team that worked on this project.  A scenario that is likely to happen again.

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    Douglas Porter P.E., M.ASCE
    Lakewood CO
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  • 27.  RE: Unit of calculation

    Posted 04-11-2018 10:46 AM
    Many presidents have advocated for a standardized system. According to this Andrew Jackson was the president that signed the bill that first required metrification in the US.

    Presidential Measurements Timeline
    NIST remove preview
    Presidential Measurements Timeline
    1790 - President George Washington called for a uniform system of currency and weights and measures - an "object of...
    View this on NIST >


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    John Helmers P.E., M.ASCE
    Director of Environmental Resources
    Olmsted County Public Works
    Stewartville MN
    ------------------------------



  • 28.  RE: Unit of calculation

    Posted 04-12-2018 10:52 AM
    Edited by Tirza Austin 04-12-2018 10:52 AM
    I was a newly Apprenticed Electrician with a year of Engineering Technical College under my belt in December of 1975.  All the trades tended to gather in one place for coffee break because it was the warm, clean spot on the job site.  One morning I overheard the carpenters complaining about the then current push by the federal government to go metric.  None of them liked it.  I was waiting for my chance to offer that I could explain in 5 minutes as much of the metric system as the common person needed.
       Before my chance arose a old carpenter groused, " You know why nobody likes like metric?"  Immediately continuing, he declared,  "Because it's too complicated!  People just can't understand it"
      "Yeah",  "Yeah",  "Yeah", were the vocal approvals!  To which a young carpenter added, "Wait 'tll our money goes metric; then we'll be ALL screwed up!"  Again the chorus of negative affirmations!
      I decide that my best bet was to keep drinking my coffee and not snicker. 
       Don't expect the U.S. to go fully metric anytime soon.

    ------------------------------
    James Justin Mercier, P.E.
    Life Member ASCE
    Sr. Life Member IEEE
    Austin Texas
    512-442-4016
    ------------------------------



  • 29.  RE: Unit of calculation

    Posted 04-12-2018 10:55 AM
    Edited by Tirza Austin 04-12-2018 10:55 AM
    One of the things that the previous round of attempted metrication revealed was an unnecessary complication of the units.  One of the things that makes customary units easy to understand is the dearth of derived units.  The last round of conversion, pushed SI with its many derived units. It is really simple to figure stresses from forces and areas when using pounds per square foot as a pressure unit (or even Newtons per square meter).  Using derived units like Pascals occludes this obvious relationship.  SI is also problematic in that the units are not practically sized like feet and inches.  While the math is simpler with metric units, the units themselves are not humanly friendly. SI uses millimeters and meters: one is too small and the other too big.  Why work in thousands or thousandths when you can work in whole numbers?

    We have to recognize that neither system is perfect.  Metric units make sense for science, since they are based on scientifically derived factors such as water boiling and freezing and dimensions of the earth.  The Celsius degree is good for weather, but has little bearing on other things.  Metric degrees are much larger forcing the use of fractions where Fahrenheit degrees do not.  While Kelvin and Celsius share a common unit, the conversion between them is still an odd number.  The metre was originally defined in 1793 as one ten-millionth of the distance from the equator to the North Pole.  This has little practical value, since things are rarely, if ever, related to the size of the globe.  Further, our Earth is not the same size as anything else to make the unit universal.  It is just as arbitrary and less useful than the foot.  The acceleration due to gravity is not a whole number in either system. It would seem the perfect system would address that, since that pervades all engineering analysis.

    In reality it makes little difference which units we use.  The things we measure and compute can be completed using either method.  One cannot argue this on the basis of one being better than the other, since each has advantages and may be better for some purposes.  The real problems revolve around communication and conversion between systems and units within the system.  This is akin to  Beta vs. VHS in that it comes down to preferences more than functionality.  Both systems work.  As has been stated throughout this discussion, the main issue is cost of changing.  Until there is a good economic case for changing, or a groundswell of public support, a change is unlikely to happen.

    ------------------------------
    Michael Byle P.E., D.GE, F.ASCE
    Tetra Tech Inc.,
    Langhorne PA
    ------------------------------



  • 30.  RE: Unit of calculation

    Posted 04-13-2018 10:48 AM
    ​Michael- Some very good points. Drawings from other countries will at times use centimeters for all measurements and it is up to the viewer to know which units they are using- much like using a slide rule when knowing where to put the decimal.

    ------------------------------
    James Worrell
    Mostly Retired
    PE, RLS (retired)
    Raleigh NC
    [jimworrell@...]
    ------------------------------



  • 31.  RE: Unit of calculation

    Posted 04-13-2018 10:49 AM
    Edited by Tirza Austin 04-13-2018 10:48 AM
    ​Since the debate on which system to use has been ongoing for well over 100 years now, it will continue to be unresolved and debated for another 100 years unless one system is set as the standard and that can only be done by having contract documents require a specific system to be used for the project.  Owners should decide the system to be used for the project and the design, construction and post-construction documents should be prepared as required by the various contracts issued for that project.  Meanwhile, having two different units of measure used on the same project for different documents will continue to allow for additional sources of confusion (errors).

    ------------------------------
    Stanley Bujalski P.E., M.ASCE
    Retired
    Thornton NH
    ------------------------------