Horizontal/Subsurface Infrastructure & Transportation

I can´t understand why in these times of computers and calculation tools, civil engineers that have been taught to do all kind of calculations, have problems with measurements units. 
------------------------------
Alvaro Villamizar-C P.E., M.ASCE
Port Coquitlam BC
------------------------------

Alvaro,
I believe that you have stated, exactly oppositely, of why there is a problem with units.
When an engineer is dependent on a computer and cannot visualize whether the result is reasonable or not, there are going to be problems.

One problem with the SI system is that the units are not humane.  The mm is too small, the meter too large for many uses, and the cm is not an official unit of the system.  This is but one example of the difficulty in using this system of units.

I have worked (in Europe and the US) using both the metric and in-lb unit systems.  It took about a month of daily use to get used to visualizing in the metric system (not the SI system thankfully, this was ages ago) and then it was quite convenient to use. It then took a couple of weeks to get back into the in-lb system when I returned to the states.  It is not easy going back and forth, and the average person does not want to spend the effort to make the jump the first time.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ
------------------------------

The centimetre is an official unit of the SI system and is used for dimensioning all over Europe. The problem is not units it is the people who use them. A much bigger problem is the use of the comma as a decimal point in Europe or the decimal point to separate hundreds from thousands etc. Thus 1.000,001 is one thousand and one thousandth, namely 1,000.001.

------------------------------
Tim Clark, FRAS, R.A., M.ASCE,
President Emeritus RIBA-USA,
Deutsche Bahn Engineering,
Bavaria, Germany.
------------------------------

Original Message:
Sent: 04-19-2018 08:45
From: Gregory Thomas
Subject: UNIT OF CALCULATION

Alvaro,
I believe that you have stated, exactly oppositely, of why there is a problem with units.
When an engineer is dependent on a computer and cannot visualize whether the result is reasonable or not, there are going to be problems.

One problem with the SI system is that the units are not humane.  The mm is too small, the meter too large for many uses, and the cm is not an official unit of the system.  This is but one example of the difficulty in using this system of units.

I have worked (in Europe and the US) using both the metric and in-lb unit systems.  It took about a month of daily use to get used to visualizing in the metric system (not the SI system thankfully, this was ages ago) and then it was quite convenient to use. It then took a couple of weeks to get back into the in-lb system when I returned to the states.  It is not easy going back and forth, and the average person does not want to spend the effort to make the jump the first time.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ
------------------------------

I stand corrected on the cm being an official unit, thank you for pointing this out.  When I was originally exposed to it on one project all units were prefixed according to powers of 3 ("m' for.001,"" for 1,"k" for 1000, etc.) but this may have been a project specific requirement.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ
------------------------------

Original Message:
Sent: 04-20-2018 02:47
From: Tim Clark
Subject: UNIT OF CALCULATION

The centimetre is an official unit of the SI system and is used for dimensioning all over Europe. The problem is not units it is the people who use them. A much bigger problem is the use of the comma as a decimal point in Europe or the decimal point to separate hundreds from thousands etc. Thus 1.000,001 is one thousand and one thousandth, namely 1,000.001.

------------------------------
Tim Clark, FRAS, R.A., M.ASCE,
President Emeritus RIBA-USA,
Deutsche Bahn Engineering,
Bavaria, Germany.
------------------------------


Original Message:
Sent: 04-19-2018 08:45
From: Gregory Thomas
Subject: UNIT OF CALCULATION

Alvaro,
I believe that you have stated, exactly oppositely, of why there is a problem with units.
When an engineer is dependent on a computer and cannot visualize whether the result is reasonable or not, there are going to be problems.

One problem with the SI system is that the units are not humane.  The mm is too small, the meter too large for many uses, and the cm is not an official unit of the system.  This is but one example of the difficulty in using this system of units.

I have worked (in Europe and the US) using both the metric and in-lb unit systems.  It took about a month of daily use to get used to visualizing in the metric system (not the SI system thankfully, this was ages ago) and then it was quite convenient to use. It then took a couple of weeks to get back into the in-lb system when I returned to the states.  It is not easy going back and forth, and the average person does not want to spend the effort to make the jump the first time.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ

------Original Message------

Alvaro,
I believe that you have stated, exactly oppositely, of why there is a problem with units.
When an engineer is dependent on a computer and cannot visualize whether the result is reasonable or not, there are going to be problems.

One problem with the SI system is that the units are not humane.  The mm is too small, the meter too large for many uses, and the cm is not an official unit of the system.  This is but one example of the difficulty in using this system of units.

I have worked (in Europe and the US) using both the metric and in-lb unit systems.  It took about a month of daily use to get used to visualizing in the metric system (not the SI system thankfully, this was ages ago) and then it was quite convenient to use. It then took a couple of weeks to get back into the in-lb system when I returned to the states.  It is not easy going back and forth, and the average person does not want to spend the effort to make the jump the first time.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ
------------------------------

Original Message:
Sent: 04-17-2018 11:36
From: Alvaro Villamizar-C
Subject: UNIT OF CALCULATION

I can´t understand why in these times of computers and calculation tools, civil engineers that have been taught to do all kind of calculations, have problems with measurements units.
------------------------------
Alvaro Villamizar-C P.E., M.ASCE
Port Coquitlam BC
------------------------------

Gregory.
The use of any kind of units depends on the job that you usually are performing. In every activity the most important is visualize the units that you use. For example, during my work as Hydraulic and Irrigation designer in many Latin American countries, I have had to use all kind of unit systems. For example for soil infiltration and rainfall, I use mm/hr or in/min, for discharge, I use m3/s and g.p.m. (pumps), m3/hr and g.p.m(sprinkler design), for distances and lengths I use m, km, feet, etc. A good idea is use metric system when you are in a Latin Country and English units if they are used in that country. In every case, I use the main unit followed by the other between brackets.

------------------------------
Alvaro Villamizar-C P.E., M.ASCE
Port Coquitlam BC
------------------------------

Original Message:
Sent: 04-19-2018 08:45
From: Gregory Thomas
Subject: UNIT OF CALCULATION

Alvaro,
I believe that you have stated, exactly oppositely, of why there is a problem with units.
When an engineer is dependent on a computer and cannot visualize whether the result is reasonable or not, there are going to be problems.

One problem with the SI system is that the units are not humane.  The mm is too small, the meter too large for many uses, and the cm is not an official unit of the system.  This is but one example of the difficulty in using this system of units.

I have worked (in Europe and the US) using both the metric and in-lb unit systems.  It took about a month of daily use to get used to visualizing in the metric system (not the SI system thankfully, this was ages ago) and then it was quite convenient to use. It then took a couple of weeks to get back into the in-lb system when I returned to the states.  It is not easy going back and forth, and the average person does not want to spend the effort to make the jump the first time.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ
------------------------------

Alvaro:
Sure we need to use the units of measurements in what ever country we operate, especially as it final results are in the units of the land.

I see the problem, which it is not, in the USA, not in the calculation arena, but in putting into effect  the final designs into construction information that the worker have grown up with. Of my 64 years in engineering and construction I spent 8 of them in the fabrication and detailing of Rebar (in USA units)  while I went to engineering school at night. During that hands on experience I bent thousands of tons of bar and detailed hundreds of significant rebar projects, all put to use without construction difficulties... A very valuable experience in visualizing the spacial aspects of the work involved in terms of carrying it over to the development construction plans for all types of projects and in effective modular dimensioning.

For the most part, engineers do not go to the field and build their design with the familiar units and the dimensioned products available in the land.  Until engineers work in the shoes for any length of time in any given land it will be appreciate what it means to work in the dimensional units practiced and available.  I believe there is too much ingrained/invested in the products and history of USA construction to ever see a change to the metric domain.

------------------------------
Allen Hulshizer P.E., F.ASCE
Consulting Structural Engineer
Chalfont PA
------------------------------

Original Message:
Sent: 04-20-2018 13:15
From: Alvaro Villamizar-C
Subject: UNIT OF CALCULATION

Gregory.
The use of any kind of units depends on the job that you usually are performing. In every activity the most important is visualize the units that you use. For example, during my work as Hydraulic and Irrigation designer in many Latin American countries, I have had to use all kind of unit systems. For example for soil infiltration and rainfall, I use mm/hr or in/min, for discharge, I use m3/s and g.p.m. (pumps), m3/hr and g.p.m(sprinkler design), for distances and lengths I use m, km, feet, etc. A good idea is use metric system when you are in a Latin Country and English units if they are used in that country. In every case, I use the main unit followed by the other between brackets.

------------------------------
Alvaro Villamizar-C P.E., M.ASCE
Port Coquitlam BC
------------------------------


Original Message:
Sent: 04-19-2018 08:45
From: Gregory Thomas
Subject: UNIT OF CALCULATION

Alvaro,
I believe that you have stated, exactly oppositely, of why there is a problem with units.
When an engineer is dependent on a computer and cannot visualize whether the result is reasonable or not, there are going to be problems.

One problem with the SI system is that the units are not humane.  The mm is too small, the meter too large for many uses, and the cm is not an official unit of the system.  This is but one example of the difficulty in using this system of units.

I have worked (in Europe and the US) using both the metric and in-lb unit systems.  It took about a month of daily use to get used to visualizing in the metric system (not the SI system thankfully, this was ages ago) and then it was quite convenient to use. It then took a couple of weeks to get back into the in-lb system when I returned to the states.  It is not easy going back and forth, and the average person does not want to spend the effort to make the jump the first time.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ

I fully agree.
The main issue arrising from the differences in units is that we loose the feeling of the results.
I work mainly with SI but I usually read books in Imperial untis and I have this problem.

------------------------------
Nick Zygouris C.Eng, M.ASCE
Structural Engineer
Lithos Consulting Engineers
------------------------------

Original Message:
Sent: 04-19-2018 08:45
From: Gregory Thomas
Subject: UNIT OF CALCULATION

Alvaro,
I believe that you have stated, exactly oppositely, of why there is a problem with units.
When an engineer is dependent on a computer and cannot visualize whether the result is reasonable or not, there are going to be problems.

One problem with the SI system is that the units are not humane.  The mm is too small, the meter too large for many uses, and the cm is not an official unit of the system.  This is but one example of the difficulty in using this system of units.

I have worked (in Europe and the US) using both the metric and in-lb unit systems.  It took about a month of daily use to get used to visualizing in the metric system (not the SI system thankfully, this was ages ago) and then it was quite convenient to use. It then took a couple of weeks to get back into the in-lb system when I returned to the states.  It is not easy going back and forth, and the average person does not want to spend the effort to make the jump the first time.

------------------------------
Gregory Thomas M.ASCE
Laboratory Director
Terrasense, LLC
Totowa NJ
------------------------------

Alvaro: 
It is not that engineers can't plug in and use any kind of numbers/units.  It is the use of these results in conveying information for construction application in the USA.  These construction units have been ingrained for so in the minds of the craftsman that they can readily envision what the dimensions represent. 

One can measure things for approximation as an example, one inch for a thumb joint, nine inches for a hand span, step off distances in either foot or yards, etc.  While these are not that accurate for construction in USA they are helpful in keeping in mind what things represent before they are laid out. The closest thing that can be envisioned is a meter and we do that by comparing it to a yard for smaller lengths.

Having been deeply involved in engineering and construction since 1954 (and still involved), I believe that the use of the fps units have been very successfully implemented for most, if not all USA major construction projects from housing, bridges, high rise to Nuclear Power Plants and that I have never come across a problem in construction that could be attributed to using the fps units to convey what is needed to build whatever.



------------------------------
Allen Hulshizer P.E., F.ASCE
Consulting Structural Engineer
Chalfont PA
------------------------------

From a Civil perspective, ​I'll blame this on a lack of applicable field experience.  Until you've stood on the end of a 10,000 foot runway, you'll never recognize the scale of it, because on your desk, the entire facility fits on a 27" monitor.

------------------------------
Alan Palmer P.E., M.ASCE
Principal Trans Engr
Stanley Consultants Inc
Muscatine IA
------------------------------

​I think tools like MathCAD may both hinder and help "unit awareness". Many people do a poor job of fashioning equations, usually opting to simply list and compute digits without considering the units. Unit-aware software helps maintain units and identify missing or misused factors.

Half of my (literal) Engineering 101 class was on using dimensions in forming/deriving/filling equations. When this is done, it really does not matter what units, or mixture of units, is used. You can compute apples plus oranges, as long as you know the proportion of apple that is equivalent to an orange.

Ironically, the people saying that we should force everyone to a single set of units are probably the ones who shortcut the most. People who understand units and math don't really have a problem switching between them. We also understand that numbers without units are meaningless.

------------------------------
John Turner CSP, P.E., M.ASCE
Dallas, TX
------------------------------

Computers can handle units like champs.  The problem occurs when manuals written for use with hand calculations tend to omit units in formulas and constants.  The computer will immediately flag a conflict.  It is not that I entered the formula wrong... it was that the formula as it appears in the manual does not display the units!  This occurs in ASCE 7 and the Aluminum Design Manual among others.

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

Original Message:
Sent: 04-19-2018 09:39
From: John Turner
Subject: UNIT OF CALCULATION

​I think tools like MathCAD may both hinder and help "unit awareness". Many people do a poor job of fashioning equations, usually opting to simply list and compute digits without considering the units. Unit-aware software helps maintain units and identify missing or misused factors.

Half of my (literal) Engineering 101 class was on using dimensions in forming/deriving/filling equations. When this is done, it really does not matter what units, or mixture of units, is used. You can compute apples plus oranges, as long as you know the proportion of apple that is equivalent to an orange.

Ironically, the people saying that we should force everyone to a single set of units are probably the ones who shortcut the most. People who understand units and math don't really have a problem switching between them. We also understand that numbers without units are meaningless.

------------------------------
John Turner CSP, P.E., M.ASCE
Dallas, TX
------------------------------

​Shame on me if I am not fully grasping the heart of this conversation, but it strikes me that the arithmetic of converting from English to Metric units and vice-versa is easy. It's the growing up thinking in one versus the other and the size standards of the products that are manufactured and used in the built environment that are the challenge. You grow up developing a "feel" for inches, feet, yards, miles, pounds, horsepower, (pecks and bushels if you work on a farm) etc., and being called upon later in life to "translate" that "feel" into different units can be a challenge, although the math of doing so, and the myriad of tools available today that will quickly do it for you is easy. But if you couple that "feel" with the fact that builders in the U.S. think (and purchase products) in terms of 2 in X 4 in (which aren't) 4 ft X 8 ft sheets, 3/4 inch thick, 3/8 and 1/2 inch diameter, etc. and consider an entire society built upon structures constructed from pieces made to those units, then the notion of conversion becomes very daunting indeed. Anyone can quickly tell you that a 4 X 8 feet sheet of plywood or drywall is 1219.2 mm X 2438.4 mm, but what you'll see in metric countries is that off the shelf sizes are 1.25 m x 2.5 m, 2.8 m, 3.0 m & 3.2 m with some even saying that a 1200 mm X 2500 mm is a 4 ft X 8 ft equivalent, but does that readily and conveniently fill a 4 ft X 8 ft hole? Some industries in the U.S., autos and electronics for example, can fairly easily convert to metric (although don't get started on things like whether a 9 mm wrench works on a 3/8 in nut). But the built environment – the infrastructure and the living spaces – is a long way away from thinking and being in metric.

------------------------------
David Vanaman P.E., M.ASCE
Assistant General Counsel
WSP USA Inc
Herndon VA
------------------------------

Original Message:
Sent: 04-19-2018 13:08
From: Chad Morrison
Subject: UNIT OF CALCULATION

Computers can handle units like champs.  The problem occurs when manuals written for use with hand calculations tend to omit units in formulas and constants.  The computer will immediately flag a conflict.  It is not that I entered the formula wrong... it was that the formula as it appears in the manual does not display the units!  This occurs in ASCE 7 and the Aluminum Design Manual among others.

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


Original Message:
Sent: 04-19-2018 09:39
From: John Turner
Subject: UNIT OF CALCULATION

​I think tools like MathCAD may both hinder and help "unit awareness". Many people do a poor job of fashioning equations, usually opting to simply list and compute digits without considering the units. Unit-aware software helps maintain units and identify missing or misused factors.

Half of my (literal) Engineering 101 class was on using dimensions in forming/deriving/filling equations. When this is done, it really does not matter what units, or mixture of units, is used. You can compute apples plus oranges, as long as you know the proportion of apple that is equivalent to an orange.

Ironically, the people saying that we should force everyone to a single set of units are probably the ones who shortcut the most. People who understand units and math don't really have a problem switching between them. We also understand that numbers without units are meaningless.

------------------------------
John Turner CSP, P.E., M.ASCE
Dallas, TX

At one time in the mid to late 1990s Caltrans was dead set on switching to metric units and some small projects  were designed and built using them. When the Alameda Corrridor project was being designed it was unclear as to whether this new convention would continue. In my case I spent most of my engineering career involved in right of way work coordinating between the engineers and the people who acquired the properties needed for projects. Since right of way work begins way out in front of design, we were unsure as to what units would be used in preparation for the legal descriptions for the property takes. Anyway I was able to convince the client to prepare two complete sets of right of way drawings one in SI and one in metric units so that we would be ready to go. The conversion factor used was really quite simple. For example a 100 ft. wide right or way was 100(12/39.37)=30.48 meters. This conversion (rounded to two decimal places) was considered adequate for surveying and property acquisition purposes. So the metric right of way plans were prepared using this ratio and we started to acquire properties using it as well. As you might imagine there was such a backlash from property owners, appraisers, and acquisition agents when they were asked to sell or dedicate a property using metric units. As far as I know Caltrans gave up on the idea after that.

------------------------------
Thomas Hanley P.E., M.ASCE
Buena Park CA
------------------------------

Original Message:
Sent: 04-20-2018 09:54
From: David Vanaman
Subject: UNIT OF CALCULATION

​Shame on me if I am not fully grasping the heart of this conversation, but it strikes me that the arithmetic of converting from English to Metric units and vice-versa is easy. It's the growing up thinking in one versus the other and the size standards of the products that are manufactured and used in the built environment that are the challenge. You grow up developing a "feel" for inches, feet, yards, miles, pounds, horsepower, (pecks and bushels if you work on a farm) etc., and being called upon later in life to "translate" that "feel" into different units can be a challenge, although the math of doing so, and the myriad of tools available today that will quickly do it for you is easy. But if you couple that "feel" with the fact that builders in the U.S. think (and purchase products) in terms of 2 in X 4 in (which aren't) 4 ft X 8 ft sheets, 3/4 inch thick, 3/8 and 1/2 inch diameter, etc. and consider an entire society built upon structures constructed from pieces made to those units, then the notion of conversion becomes very daunting indeed. Anyone can quickly tell you that a 4 X 8 feet sheet of plywood or drywall is 1219.2 mm X 2438.4 mm, but what you'll see in metric countries is that off the shelf sizes are 1.25 m x 2.5 m, 2.8 m, 3.0 m & 3.2 m with some even saying that a 1200 mm X 2500 mm is a 4 ft X 8 ft equivalent, but does that readily and conveniently fill a 4 ft X 8 ft hole? Some industries in the U.S., autos and electronics for example, can fairly easily convert to metric (although don't get started on things like whether a 9 mm wrench works on a 3/8 in nut). But the built environment – the infrastructure and the living spaces – is a long way away from thinking and being in metric.

------------------------------
David Vanaman P.E., M.ASCE
Assistant General Counsel
WSP USA Inc
Herndon VA
------------------------------


Original Message:
Sent: 04-19-2018 13:08
From: Chad Morrison
Subject: UNIT OF CALCULATION

Computers can handle units like champs.  The problem occurs when manuals written for use with hand calculations tend to omit units in formulas and constants.  The computer will immediately flag a conflict.  It is not that I entered the formula wrong... it was that the formula as it appears in the manual does not display the units!  This occurs in ASCE 7 and the Aluminum Design Manual among others.

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


Original Message:
Sent: 04-19-2018 09:39
From: John Turner
Subject: UNIT OF CALCULATION

​I think tools like MathCAD may both hinder and help "unit awareness". Many people do a poor job of fashioning equations, usually opting to simply list and compute digits without considering the units. Unit-aware software helps maintain units and identify missing or misused factors.

Half of my (literal) Engineering 101 class was on using dimensions in forming/deriving/filling equations. When this is done, it really does not matter what units, or mixture of units, is used. You can compute apples plus oranges, as long as you know the proportion of apple that is equivalent to an orange.

Ironically, the people saying that we should force everyone to a single set of units are probably the ones who shortcut the most. People who understand units and math don't really have a problem switching between them. We also understand that numbers without units are meaningless.

------------------------------
John Turner CSP, P.E., M.ASCE
Dallas, TX

​Like converting a written text from one language to another there is a caution in the cliché "lost in translation".  That caution must be emphasized and addressed by engineers, most especially Civil, in preparing documents for construction.  Already noted here in several other posts, the translation from one unit to another can be easily misread by construction tradesmen.  The design engineer needs to be aware of that fact and prepare documents that avoid the lost in translation error.

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

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM
------------------------------

This is a fun discussion.  Brings back lots of memories.  I've seen two efforts to make the switch.  The last in the 90's.  In my early experience as a surveyor in California I've had to work in spanish units of measure, that went to rods and chains and then to feet.  Never in inches except to measure the size of a witness tree. When bringing plans to the public we had to convert feet to feet and inches.  When doing projects in the 90's we found that most hardware was built to metric units and labeled in nominal inch dimensions for the American public.  100 mm pipe was 4 inch. When we attempted to comply with the State's requirement to use metric we did but the contractors attempted to convert our plans back to feet and inches in the field.  We gave them metric tape measures hoping to avoid errors.  That helped some but the resistance was there.  We can stay in our American measurement system or convert to what most everyone else uses.  Probably makes little difference.  But if we really want to convert we must do it and not waffle as we have ever since the  US adopted the metric system in 1975.

------------------------------
Wayne Peterson P.E.
CE Retired
------------------------------

Original Message:
Sent: 04-23-2018 08:41
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM
------------------------------

I spent a year in South Africa in the mid 80's.  They had fairly recently switched to metric.  They just did it and everyone complied.  I had some experience in Thailand with it so It wasn't too problematical.  My wife learned that 250 cc was a cup.  500 g was 1 pound, etc.  
The conversion is easy if one remembers that matric is just 10% greater than English.  e.g., 1 meter = 1 yard + 10% (i. e., 3.3 ft). 1 liter = 1.1 quarts, i kilo = 2.2 lbs. etc.  That even works when converting deg C to deg F except you have to adjust for the freezing point being 32 deg F

------------------------------
John Nelson Ph.D., P.E., D.GE, F.ASCE
PRINCIPAL ENGNR
[Engineering Analytics, Inc.]
Wellington CO
------------------------------

Original Message:
Sent: 04-24-2018 09:47
From: Wayne Peterson
Subject: UNIT OF CALCULATION

This is a fun discussion.  Brings back lots of memories.  I've seen two efforts to make the switch.  The last in the 90's.  In my early experience as a surveyor in California I've had to work in spanish units of measure, that went to rods and chains and then to feet.  Never in inches except to measure the size of a witness tree. When bringing plans to the public we had to convert feet to feet and inches.  When doing projects in the 90's we found that most hardware was built to metric units and labeled in nominal inch dimensions for the American public.  100 mm pipe was 4 inch. When we attempted to comply with the State's requirement to use metric we did but the contractors attempted to convert our plans back to feet and inches in the field.  We gave them metric tape measures hoping to avoid errors.  That helped some but the resistance was there.  We can stay in our American measurement system or convert to what most everyone else uses.  Probably makes little difference.  But if we really want to convert we must do it and not waffle as we have ever since the  US adopted the metric system in 1975.

------------------------------
Wayne Peterson P.E.
CE Retired
------------------------------


Original Message:
Sent: 04-23-2018 08:41
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM

Wayne Peterson presents the exact same problems we had when the Texas Department of Transportation tried to go metric.

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

Original Message:
Sent: 04-24-2018 09:47
From: Wayne Peterson
Subject: UNIT OF CALCULATION

This is a fun discussion.  Brings back lots of memories.  I've seen two efforts to make the switch.  The last in the 90's.  In my early experience as a surveyor in California I've had to work in spanish units of measure, that went to rods and chains and then to feet.  Never in inches except to measure the size of a witness tree. When bringing plans to the public we had to convert feet to feet and inches.  When doing projects in the 90's we found that most hardware was built to metric units and labeled in nominal inch dimensions for the American public.  100 mm pipe was 4 inch. When we attempted to comply with the State's requirement to use metric we did but the contractors attempted to convert our plans back to feet and inches in the field.  We gave them metric tape measures hoping to avoid errors.  That helped some but the resistance was there.  We can stay in our American measurement system or convert to what most everyone else uses.  Probably makes little difference.  But if we really want to convert we must do it and not waffle as we have ever since the  US adopted the metric system in 1975.

------------------------------
Wayne Peterson P.E.
CE Retired
------------------------------


Original Message:
Sent: 04-23-2018 08:41
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM

BTW, did you notice that for automotive tires, the width of the thread is given in millimeters, but the wheel diameter in inches?
Just the kind of thing that drives the mathematical purists over the edge, but there it is.
Anybody know why tires are labeled this way?

------------------------------
Hans H. Coucheron-Aamot
[Retired]
Albuquerque NM
------------------------------

Original Message:
Sent: 04-25-2018 08:52
From: James Mercier
Subject: UNIT OF CALCULATION

Wayne Peterson presents the exact same problems we had when the Texas Department of Transportation tried to go metric.

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


Original Message:
Sent: 04-24-2018 09:47
From: Wayne Peterson
Subject: UNIT OF CALCULATION

This is a fun discussion.  Brings back lots of memories.  I've seen two efforts to make the switch.  The last in the 90's.  In my early experience as a surveyor in California I've had to work in spanish units of measure, that went to rods and chains and then to feet.  Never in inches except to measure the size of a witness tree. When bringing plans to the public we had to convert feet to feet and inches.  When doing projects in the 90's we found that most hardware was built to metric units and labeled in nominal inch dimensions for the American public.  100 mm pipe was 4 inch. When we attempted to comply with the State's requirement to use metric we did but the contractors attempted to convert our plans back to feet and inches in the field.  We gave them metric tape measures hoping to avoid errors.  That helped some but the resistance was there.  We can stay in our American measurement system or convert to what most everyone else uses.  Probably makes little difference.  But if we really want to convert we must do it and not waffle as we have ever since the  US adopted the metric system in 1975.

------------------------------
Wayne Peterson P.E.
CE Retired


Original Message:
Sent: 04-23-2018 08:41
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM

And, why are some of the nuts and bolts in a modern American car engine English while others are metric?

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

Original Message:
Sent: 04-26-2018 07:57
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

BTW, did you notice that for automotive tires, the width of the thread is given in millimeters, but the wheel diameter in inches?
Just the kind of thing that drives the mathematical purists over the edge, but there it is.
Anybody know why tires are labeled this way?

------------------------------
Hans H. Coucheron-Aamot
[Retired]
Albuquerque NM
------------------------------


Original Message:
Sent: 04-25-2018 08:52
From: James Mercier
Subject: UNIT OF CALCULATION

Wayne Peterson presents the exact same problems we had when the Texas Department of Transportation tried to go metric.

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


Original Message:
Sent: 04-24-2018 09:47
From: Wayne Peterson
Subject: UNIT OF CALCULATION

This is a fun discussion.  Brings back lots of memories.  I've seen two efforts to make the switch.  The last in the 90's.  In my early experience as a surveyor in California I've had to work in spanish units of measure, that went to rods and chains and then to feet.  Never in inches except to measure the size of a witness tree. When bringing plans to the public we had to convert feet to feet and inches.  When doing projects in the 90's we found that most hardware was built to metric units and labeled in nominal inch dimensions for the American public.  100 mm pipe was 4 inch. When we attempted to comply with the State's requirement to use metric we did but the contractors attempted to convert our plans back to feet and inches in the field.  We gave them metric tape measures hoping to avoid errors.  That helped some but the resistance was there.  We can stay in our American measurement system or convert to what most everyone else uses.  Probably makes little difference.  But if we really want to convert we must do it and not waffle as we have ever since the  US adopted the metric system in 1975.

------------------------------
Wayne Peterson P.E.
CE Retired


Original Message:
Sent: 04-23-2018 08:41
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM

This third round of discussions is once again interesting - in both funny and serious ways. Many of you have seen this piece of 1982 USACE technical note. I have attached it for ready reference - showing how Federal Gov and agencies were serious in the implementation of the SI system. Perhaps they saw the necessity of streamlining the units of measures early on, after the adoption of SI system in 1960.

Translation of engineering calculations to construction has often been mentioned as the major hindrance. It indeed can be, because of many practical reasons. The question is how should one address this hindrance/problem (if one thinks this as such). Perhaps this NIST website indicating some useful references, is helpful in this regard.

https://www.nist.gov/pml/weights-and-measures/everyday-estimation

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

Original Message:
Sent: 04-26-2018 07:57
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

BTW, did you notice that for automotive tires, the width of the thread is given in millimeters, but the wheel diameter in inches?
Just the kind of thing that drives the mathematical purists over the edge, but there it is.
Anybody know why tires are labeled this way?

------------------------------
Hans H. Coucheron-Aamot
[Retired]
Albuquerque NM
------------------------------


Original Message:
Sent: 04-25-2018 08:52
From: James Mercier
Subject: UNIT OF CALCULATION

Wayne Peterson presents the exact same problems we had when the Texas Department of Transportation tried to go metric.

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


Original Message:
Sent: 04-24-2018 09:47
From: Wayne Peterson
Subject: UNIT OF CALCULATION

This is a fun discussion.  Brings back lots of memories.  I've seen two efforts to make the switch.  The last in the 90's.  In my early experience as a surveyor in California I've had to work in spanish units of measure, that went to rods and chains and then to feet.  Never in inches except to measure the size of a witness tree. When bringing plans to the public we had to convert feet to feet and inches.  When doing projects in the 90's we found that most hardware was built to metric units and labeled in nominal inch dimensions for the American public.  100 mm pipe was 4 inch. When we attempted to comply with the State's requirement to use metric we did but the contractors attempted to convert our plans back to feet and inches in the field.  We gave them metric tape measures hoping to avoid errors.  That helped some but the resistance was there.  We can stay in our American measurement system or convert to what most everyone else uses.  Probably makes little difference.  But if we really want to convert we must do it and not waffle as we have ever since the  US adopted the metric system in 1975.

------------------------------
Wayne Peterson P.E.
CE Retired


Original Message:
Sent: 04-23-2018 08:41
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM

​This brings back memories of my years as Chief Engineer of the Maryland SHA (MDOT). In the mid-1990's a big push was to convert all plans to metric as well as all the signs on the highways and freeways. Handling the plan issues was simple by comparison since their are tens of thousands of signs on the Interstate system as an example.  Many states charged ahead and began replacing signs with metric units while other states held off. In the mean time politicians heard back from their constituents that the metric versions were confusing and the DOTS then had to go back and install the original signs or scrap the installation of the new signs. Many states wasted millions of dollars in this false start. Maryland held back so as to not be on the "bleeding edge" of this change.


------------------------------
Douglas Rose Senior Vice President
CM/CI Practice Lead
JMT
Hunt Valley MD
------------------------------

Original Message:
Sent: 04-24-2018 09:47
From: Wayne Peterson
Subject: UNIT OF CALCULATION

This is a fun discussion.  Brings back lots of memories.  I've seen two efforts to make the switch.  The last in the 90's.  In my early experience as a surveyor in California I've had to work in spanish units of measure, that went to rods and chains and then to feet.  Never in inches except to measure the size of a witness tree. When bringing plans to the public we had to convert feet to feet and inches.  When doing projects in the 90's we found that most hardware was built to metric units and labeled in nominal inch dimensions for the American public.  100 mm pipe was 4 inch. When we attempted to comply with the State's requirement to use metric we did but the contractors attempted to convert our plans back to feet and inches in the field.  We gave them metric tape measures hoping to avoid errors.  That helped some but the resistance was there.  We can stay in our American measurement system or convert to what most everyone else uses.  Probably makes little difference.  But if we really want to convert we must do it and not waffle as we have ever since the  US adopted the metric system in 1975.

------------------------------
Wayne Peterson P.E.
CE Retired
------------------------------


Original Message:
Sent: 04-23-2018 08:41
From: Hans Coucheron-Aamot
Subject: UNIT OF CALCULATION

The US market is large enough to support staying with the existing "English" units for most trades. Those who need to use the metric system to integrate with international usage for some reason can readily do so on their own
You hardly noticed when Detroit went metric, did you?

One big problem when we had the big drive for everybody to go metric was that the people in charge of that program decided to outdo the Europeans and go really rigorously scientistic and came up with units I never heard of in Europe growing up. At least so in the highway business, and these units indeed did not make much practical sense and were difficult to use. No wonder this program met with widespread resistance and political opposition.


------------------------------
Hans Coucheron-Aamot P.E., M.ASCE
Sr Civil Engr
Albuquerque NM

​An interesting book for respondents and viewers to the original question is entitled "Measure for Measure- a small book of 864 pages dedicated entirely to global measuring systems. It includes measuring systems for countries around the world- current, recently historical, and ancient.  Conversion factors are shown. The book highlights the need or a uniform system- especially the SI system. A few of the many units of linear measurement are: bhar (Sumatra), elle(Germany),yote (Cambodia), ungul (India), and totchka (Russia). In the USA, some current and historical linear measurements in addition to feet and inches are: mile, chain, rod, furlong, fathom, link, are, league, perch, cable length, arpent (Louisiana), and vara (Texas and California).

The authors of the book are Richard Young and Thomas Glover and the publisher is Blue Willow, Inc., Littleton, Colorado, USA

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