engineering design

telling old stories - part II

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part II
	Sometimes the names were changed to protect the identy of living people and surviving companies. A similarity with historical facts is possible. The author is known to the editor but his name will not be given away.

Who is the best engineer you know?

The answer to the question above is hands down, far and away, Milton Renneburger. Milton was a structural engineer at F.D. Cow Company and he had the most organized mind I have ever known (I omit any German engineers I know for this was in the past.) When Milton had a job to do that was a bit out of the way for him, for example to design some fireproof doors with a pane of glass, he hit the catalog files, specifications, the National Building Code, the Fire Code, and with all this information at hand he prepared a sheet which combined all the information in one place so that the next time a fire door had to be designed, it was there. He did this with everything with the result that he had the best files in the office.

He began to do his designs on the drafting board on tracing paper 11 inches high and as wide as necessary for the job he was doing. The result was that he had files of most of his later designs with comments. They were invaluable. When I left he company in 1956 - but returned in 1961 to work during the summer he had enlarged his collection of loose leaf binders to 5 or 6. I understand that in time he got to fill a binder for almost every letter of the alphabet.

One day, the boss asked Milton to check the support ring for the Chalk River reactor. This was a plate girder which was in the form of a large circular ring which was supported on 6 or 8 point supports. The file with design notes was copious for two physicists had spent about the equivalent of 1 man-year on this job. Someone discovered that the ring had never been checked and there was a couple of million dollars of steel and concrete on that ring.

Milton had a unique approach. He looked over the notes for a while then disappeared from the office. He went to the Engineering Institute of Canada Library on Mansefield Street and spent the afternoon reading. The next day he started making one of his famous sheets that dealt with methods of analyzing ring structures. I still have them at home somewhere. The method he found was a paper by some lady named Venturii who did a master's degree at the University of Michigan on the analysis of rings. Her approach was to use a variation of Moment Distribution, but this was a real rat's nest for there were three moments at each end of the curved segment a total of six on each member and therefore for a balance of one moment there could be 5 carry-overs to all the other moments. It sounds messy, but you have to realize that in the mid 1950's the only computer we had was a mechanical machine that was filled with gears that spun on and on.

By the end of the second day the job was complete and I have always thought that his approach of getting into the Library was a very efficient one. Milton was a graduate of the University of Manitoba, like Phil Larionov and Dave Miller, one of the engineers for whom I worked. F.D. Cow Company slowly lost more and more work as time went on and eventually they were bought by AMA who owned other Montreal engineering companies and decided to close it down. The first one to be fired was Milton Renneburger, but I imagine he would have been around retirement age, but would certainly not have any trouble in finding another job.

Backfiring classroom stories …

Here is one story about Miro Davie's comment the class room backfiring on him. One of my classmates was a very witty fellow named John Bate. Naturally his nickname was "Master Bate". His father was a clergyman who had the magnificent title of ,"The Venerable Archdeacon of the City of Saint John." What a handle that was, it would be right at home in this country.

One of our courses in 1959 was, "The Engineer in the Community" and dealt once a week with the Act, the Bylaws and the structure of the Association, the Learned Societies of Canada (Are there any?) etc., and it was the one lecture of the week when students had to leave off the ubiquitous red UNB jacket/windbreaker and wear a shirt, tie and jacket to class. I suppose the thought was that for such a weighty subject, students should try to project the image of an engineer.

The class was taught by various professors and one that stands out to this day was Miro Davie who being very fashionable wore a light blue suit to class. It was powder blue or maybe Wedgewood blue and dated to the times when mens' attire ran to pastel shades. The free form of the talk led to Miro ruminating on the first job, which he had after graduation, at Canadian Bridge in Walkerville. He went on about how his first month's paycheck was some small amount - it would have been around 1943 - of $200.00. Then he said that he went out and bought a new suit with his first pay check. As quick as a flash, John Bate came out with, "Was it blue?" That totally broke up the class into hoots of laughter and Miro totally lost it. He tried a few lame comments about John Dieffenbaker, thePrime Minister of the time for John Bate belonged to the Progressive Conservative Party on campus, but he could never top the comment, "Was it blue?"

John visited UNB a few years ago in the position of President of ASTO. He lived in London, Ontario where he had a small consulting business. I wonder if he is still known as "master"?

Marking Problems …

I graduated in 1960 and was hired as a lecturer in 1960. Because Miro Davie was on a sabbatical at Stanford, I was given his 5th year steel design course to teach. Of course my background was a bit different from most students (I am obviously a slow learner, as you may have detected), so the steel design course caused me no terror at all in the classroom.

Upon entering the class, the first comment I hear was from Jim Fraser (now retired from the position of Chief Bridge Engineer at DOT - and formerly Jana's boss), who said, "Jesus Christ look who is teaching this course." Jim had a colourful vocabulary as did his daughter. As I looked out across the class, I saw many familiar faces.

At UNB in the 1950's a student could fail three courses and write supplemental examinations. If he passed two exams, he could carry the third course and continue with his program. If he had two failures he repeated the entire year including all his passed courses. [NOTE: WHERE THE WORD HE IS USED IN THIS DOCUMENT, IT IMPLIES THAT THE WORD SHE IS ALSO VALID. There were very few "she's" in those years]

Just a little political correctness there! So, there was Larry Anstroem a former lab partner in Physics 100, Rod Bates another lab partner from the past. There were many people whom I had know as partners. But, I decided that the line across the front of the classroom was what separated me from them and so I never looked back.

Being young and foolish, and being in a time before we had graduate student slaves to do the marking, I gave a problem of designing a steel structure for a warehouse. It was a rigid frame with a sloping roof. I required a complete design brief with all calcuations and figures, just as was done in the real world.

Of course, as you know checking 40 separate design briefs is a terribly time-consuming problem for every one can be different and it takes time to get into the mind of the person who did the origianl work. But there were compensations.

One brief was an absolute work of art. The man had a "hand" and his drawings were magnificent. The calculations were well done and each page was a joy to read. He got top marks for his effort.

Later in the pile I came across another brief that was hastily thrown together and it had a certail resemblance to one I had already read. I searched through the pile and found that the scribbled job was a copy of the magnificent one I had read a few days earlier. So, I checked and found that line for line, everything had been copied. I ended up with a snarky comment that if he wanted to see his mark he should see Don's design.

In 1967, Frank Nathine came to UNB from the University of Maine where he had been working for a year until the boys at home could wangle him a position in Civil Engineering. We shared an office for part of the summer until everything was straightened out in the Fall. Of course he was, and is, a rare individual of whom the less said the better, but his rise in the heirarchy has been significant: Head of the Transportation Group (What honour is that?); Dean of Engineering for about 12 years; Head of the Sunday School at St. Anne's Anglican Church; Dean of Graduate Studies; Vice President of Research; Bag man for the Liberal Party of NB; Member of the Academy of Engineering; ........ fill in your own blanks for the rest of his accomplishments. He was never Head of the Department of Civil Engineering - in fact as Dean and member of the Department he worked for me and as Dean, I worked for him. Figure that one out. Frank was in that steel design class and his was the messy scribble of a design brief. No "hand" at all.

It was not until many years later - maybe 25 years or so that he told me the story of the design brief. The man with the "hand" was Don. He was on the UNB hockey team and as these fellows are either on the road or practising every night, he seldom had time to do his assignments. So, the night before the hand-in date for the design brief, he called Frank and asked if he could borrow his brief just to check some of his figures. In his past, Don had been a draftsman somewhere and so had developed his style of printing and drawing.

Well, the upshod of the incident was that Nathine was the originator of the design brief and Don had copied it totally, line by line.

So, the moral of the story is to be very cautious when accusing students of plagiarism for you may have the wrong man.

More lies - no make that the product of an aged memory.

During the summer of 1946 when I was between grades 10 and 11 in high school, my father got me a job in the machine shop at Canadair. The plant was located beside the old Cartierville airport where my parents would occasionally take me on Sundays in the 1930's to look at the old biplanes that went back and forth there. I think that Bombadier now does the aircraft business in that location.

My job was to do minor jobs in the machine shop. The jobs were all assembled in cardboard boxes of various sizes along with a blueprint, and maybe a jig or fixture. It was simple work involving drilling holes of a given size in a particular piece of steel, aluminum, or magnesium.

One day I was given the task of working with an elderly gentleman who appeared to be new in the shop. The job was to remove the burrs from thousands of deicer bolts all of which were arranged on the bench and floor around the bench.

At this time Canadair was producing an airplane called "The North Star" which was a four engine propeller driven aircraft. In time, it was used by Air Canada on the flights from Montreal to Fredericton. The deicer bolts were strange things: imagine a bolt about 0.25 in in diameter about 1.25 in. long threaded on the outside. It had a flat head at one end in which there was a threaded hole into the shank of the bolt, and on the other end of the bolt the diameter was reduced to maybe 3/32 in. This end had a slot which had been made by a milling machine and when the mill went through the material, it left a burr that was a little flat piece of aluminum that had to be removed. That was our task, and there were literally thousands of these things.

The old gentleman was using a file to remove the burrs and it took several swipes with a file to get the burr off. The finished bolt went into a box and the next one taken from one of the full boxes around us. The whole operation probably took him two minutes per bolt. I started the same way with a file, but then realised that the burrs could be almost taken off with strong finger nails. So, after one day with a file, I brought in a jack knife and it was only a matter before one box was finished in about half an hour while he was still filing away. A day or two later he asked me not to go so fast as he wanted the job to last as long as possible for he had only been hired for that job.

To me, I could not get through the job fast enough, but to him it meant that he had employment and who knows how important that was to his life. I lived at home, was dropped off at the plant when my father went to work and was picked up in the evening when we went home, so my interest was totally different to his. At the time, the social implications of that work did not really enter my mind.

One task that I will remember all my life was the day that the foreman gave me a box of steel links that had been in the rain somewhere and had a light cover of rust. These were made from a steel bar about 1 inch wide and maybe 4 or 5 inches long. In a side view the link had a boss on each end about 1 in long - on one end the boss was on the top of the bar and at the other end on the bottom. The centre of the link was about 0.25 in thick so it looked as if a bar 1 in wide by 3/4 in thick had been partially milled out from each end to produce the bosses. I was directed to a belt sander to remove the rust.

This was a sander with pulleys above each other - unlike a wood sander where the belt is horizontal. This one had a belt that was vertical and was about 12 inches wide. Across the top of the belt above the pulley was a tube from which soluble oil could be dispersed. Soluble oil mixes with water and has the colour and consistency of milk. It is used on all machines to keep cutters and lathe bits cool in metal oprations. The sand also had a horizontal table about 8 inches deep by 12wide across the width of the belt. With the belt running and the oil spraying on the belt there was a tremendous spray bouncing up from the table on which I held the pieces to be cleaned of rust. So, the foreman got me a yellow raincoat and some rain pants and a pair of goggles and I set to work. It was hell for the whole machine vibrated back and forth and the spray of oil was such that the goggles were useless - they had no windshield wipers!

While working on this job, one of the layout men came to me with a casting that had four legs about 6 inches long each sloped in two directions from a central piece. Something like a dog without a head. Castings usually have a line where the separate parts join and as he was going to drill holes in the bosses at the ends of the legs, he wanted to touch them up on the sander. No problem, as I was glad to get away from that sander for it seemed to have a life of its own. Little did I know!

After snading all the bosses on his box of parts, he left and I returned to my steel sanding. What I did not know what that the parts he was working on were of a magnesium alloy and the bits of grit from sanding had landed on the reservoir of soluble oil in the base of the sander. So, when I sat down with the next piece of steel, a spark went down onto the bits of magnesium alloy that were floating on the surface of the oil and - POOF! I was so surprised that I tipped the box I was sitting on and fell backwards on my back on the floor of the shop. The piece I had been touching on the belt was pushed into the belt which then jammed on the table and ripped the belt into several pieces and was flapping around the pulleys.

Nothing was hurt and it was only a matter of replacing the belt on the sander to get the job finished. I imagine that my actions in the shop gave many people a lot of laughs. But, it gave me a healthy respect for moving machinery.

The other event that impressed me was that I started in the shop at 65 cents an hour and because of a union contract my rate was raised to 75cents an hour a few weeks after starting work. That was impressive and perhaps that is the reason that I favour unions. From my later view of the administration building from the Chair of the CE department I always thought that without the Faculty Union we would have been in a worse condition than we were. I think I am really a closet Socialist.

Enough yarn spinning for now. Sometime I will tell you the story of how I got the strap while in school. I will bet that kids have never heard of the strap in school these days. It would traumatise the poor dears, after all, kids have rights today.

From the events of a misspent youth.

Another one!

I mentioned that working on a construction job as an inspector or resident engineer was an experience that every engineer should have. In the end, it is working with people that makes life interesting, and by meeting all kinds of people each with their own agenda of how the project should be run has the tendency to round off the rough spots of a young engineer's character. Here is an example.

During one summer I worked as an inspector/checker/general dogsbody on the construction of a grain elevator in Quebec City. One of my tasks was to do concrete tests and prepare concrete cylinders for the testing company. Three cylinders were made at various intervals of time and eventually these were tested elsewhere at seven days and twenty eight days. Considering that about 900 cubic feet of concrete was being placed continuously every hour during the slip forming of the walls, the impact of a low cylinder strength at seven days was a warning that in twenty eight days the strength was to be watched carefully, but overall what could really be done? There was no question of removing the concrete from the structure, even if it was known where it was located. Fortunately that scenario did not occur very often.

As a concrete inspector on the night shift one task was to check the slump of the mix. I believe the required slump was about 3.5 inches. A fairly stiff mix was required for slip forming. The slump test is a standard part of every civil engineering undergraduate laboratory programme at the University. A hollow sheet metal cone of standard ASTM dimensions (12 in high and about 3.5 in at the top and maybe 6 in at the bottom) is filled one third with the concrete and rodded 25 times with a 5/8 in rounded rod. This process is repeated until the cone is filled. Then the cone is lifted off and placed beside the slumping mass of concrete. The distance between the top of the cone and the top of the mass of concrete is the measured slump.

One night I made the test and found that the slump was of the order of 6 inches which was well over the required limit. This was mentioned to Bob Caliper the night superintendent of the job. Bob was an old man (to a young whippersnapper of about 28) who was big and fleshy. He wore glasses that seemed to have been stepped on for they did not seem to fit his face well. [These are recollections of a failing memory but theye are the chief characteristics that I remember]. Bob went to the hopper where the concrete was being loaded and took a handful of it. He looked at it in the sparce lighting of the night, he rubbed it between his fingers, he took a bit of it and ground it between his teeth and then said, "That's good concrete." I reminded him that the slump was too large and he said it was fine.

Then he proceeded to do the slump test that I had just done. More new concrete, more rodding in three layers and then he began to lift the cone off the concrete, not in one single motions as I had, but half an inch at a time. In about two minutes he had the cone off and there was the concrete standing at about a 1 in. slump. "I told you it was good concrete", he said.

I immediately went back to the office to re read the specifications for doing the slump test and there was nothing said about the rate at which the cone should be removed. Bob was lifting the cone just enough to allow the bottom 0.5 in to slump, then moving another half inch to allow the concrete to slump against the sides of the cone, and so on. The concrete was supported by the cone most of the way. An important lesson!

The concrete being supplied was from a ready-mix company that was located across the Chareles River in Quebec from the construction site. They had six and sometimes more trucks on a continuous run back and forth between the ready mix plant and the site. One hot afternoon during the slip there was no concrete. We waited and waited and finally someone called the plant and the report was that there were six truck loads of concrete on the road somewhere. Of course with slip forming the forms have to keep moving so that the concrete will not stick to the forms and to repair that is a major effort and expense.

The problem was that river traffic takes precedence over road traffic and on that afternoon a ship had gone down the river to the St. Lawrence and the swing bridge on the street had opened. It was around four in the afternoon and so there was a horrendous traffic jam on both sides of the bridge and among that mess of vehicles were the six concrete trucks.

Everyone was looking down the street to see when the trucks would appear and sure enough three of them came barrelling to the site with dust flying everywhere. The first truck was not turning the mixer for the engine running the mixer had run out of gas. So he borrowed some gas from the site and charged his gas tank. Before doing that, however, he jumped up on the truck and put in about 150 gallons of water into the mix. Doing that in front of a concrete inspector gives one a sense of power, and so that batch of concrete was rejected. Back he went to the ready mix plant.

Over the days of the climb, I rejected several truck loads of concrete largely on the basis of overmixing, or too high temperatures - both of which were according to the specifications. One day the sales manager for the Ready Mix company visited the site and I asked him what was done with the concrete that was returned to the plant because of overmixing (I could check the time the truck had left the plant) or high temperature - which was meassured with a thermometer put into the mix. "No problem", he said. "We have a big tank where we wash the cement out of the aggregates and then recycle the aggregates." That sounded like a very sensible operation.

Near the end of my stay on the job - I had to return to complete my University programme - the Resident Engineer and I visited the Ready Mix plant. It was impressive with automatic mix design, electronically controlled scales, etc. I asked the operator where the big tank was that was used for washing the cement out of the rejected concrete and his answer was, "Oh, we don't do anything, but may put a little more cement in the original mix in the truck and send it back."

So much for trying to do a good job as an inspector.

The facile way that construction superintendents have with the truth is amazing. In constructing 24 concrete bins that were 24 ft in diameter, there were vertical deformed rebars spaced around the perimeter of the walls at about 9 or maybe 12 inches on centres. The horizontal bars were plain rods about 0.25 in in diameter about 27 ft. long each. Once the concrete in a particular cell reached the working platform - which was always rising at a constant rate - three of the plain bars would be sprung into place around the vertical bars and held in place with two chain links, one at each end of the splice. The bars were not actually bent into a permanent shape, but held by the chain links. Eventually, the slip form would rise and when the last cell had been placed there would be a distance of 5 or 6 inches of concrete to be placed on the first cells that made the spacing of the horizontal bars 5 or 6 inches. As I remember, the spacing was 5.5 inches at the bottom of the cells and wider apart higher up. So the actual spacing was 5in and 6in to give the proper average spacing.

This procedure was repeated day and night until the 24 cells had reached a height of 103 or 105 feet above the foundation. That seemed to be a standard height and was probably based on the capacity required in the storage cells. The Farter Construction Company had this operation worked out very well and all went with efficiency. One day when the first 24 cells had been completed I noticed there was a pile of quarter inch plian reinforcing bars lying beside the elevator. When asked about them, the superintendent said that they were "extras" in case they needed any more steel. Yeah! If one has 24 cells and one layer of steel is missed, for whatever reason, there will automatically be 24x 3 = 72 quarter inch bars 27 ft long. I did not count them, but should have to see what his explanation might be.

Another Chapter in a misspent life.

In the following story all names were changed to protect the identy of living people and surviving companies. A similarity with historical facts is possible. The author is known to the software house but his name will not be given away.

The pictures of "big bracing" brought back some memories of work at Domino Building around 1949 or 1950. A new central heating plant was being designed for the House of Parliament in Ottawa and it was located at the foot of a bluff beside the river. This had trusses which spanned the width of the building, but carried at the second or third panel point a vertical hanger to which plate was suspended in the form of a parabola - attached to the truss at one side and to a beam between columns at the other. This formed a coal bunker which, through a "weight larry", fed coal into the various boilers below. They were located along the side wall. The coal was fed into the bunkers below the truss by a conveyor system. The tripper of the conveyor was housed in some kind of a huge zippered cover which was designed to reduce the amount of coal dust.

The fellow detailing the truss (Jim Markely) found that the forces in the end diagonals were so large that the gusset plates touched each other. The truss was double plane and the rivets were 7/8 in, so there was lots of force being transmitted. Someone in our office called the design office to complain about the gussets being so large and an engineer was sent down to out office to look into the problem.

I don't remember his name, but he was an Englishman - and there were many around that time because after the war there was a lack of detailers and designers available. The company routinely made trips to England to recruit people. Anyhow, this fellow proceeded to calculate the truss as a frame and did a moment distribution analysis. I well remember his design sheets which were almost black with figures. You can imagine the carry overs for a truss with members going in all directions. I imagine that his fixed end moments were determined from the displacements of the joints - probably from a Williot-Mohr analysis for were are talking slide rule times here.

Following the first analysis he found the additional forces in the truss members arising from the fixity of the joints. This led to another set of displacements and then another moment distribution and so on. I think he did this through three iterations and then produced a set of plates - down the end diagonals where the gusset plates were touching, along the bottom and top chords in the outer parts of the truss.

For the detailer this meant adding four narrow plates on the inside of each flange because the gusset plates were on the outside of the flanges. Eventually all was fixed up and the detail drawing sent off to the consultant - a man named Red Pooster, in Montreal. A few days later the detail drawing came back with "rejected" stamped on the drawing and the note in big red letters, "Remove this superfluous steel plate!".

The squad boss immendiately called Mr. Rohnson, the chief design engineer, who came into the office to look at the analysis and the truss details. After doing this for a few minutes, he called Mr. Rooster to tell him that his design did not take secondary stresses into account and the reinforcement was needed. That led to an argument over the telephone to which the entire office was privy for we had an open office with the boss's desk surrounded by all the detailers and checkers. The talk became so heated that Johnson was holding the telephone at arms length because he was yelling so loudly that everyone in the office could hear the conversation. It was amusing.

The extra plates were taken off - more work for the detailer - and thinking about the problem it was obvious that some plastification might take place where high stresses occurred and that would have no lasting effect on the performance of the truss. This was a bit before the plastic design concept was very strong so maybe Pooster knew more about the problem than Rohnson. But the general rule at D.B. was, "Steel is sold by the pound." so to load up a bit now and then was good for business - but not for Red Pooster.

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author:	Eastern Filosofer