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While in general I agree with you. I'd just like to mention one counter argument, which the rigidity of the code in some cases will help to protect against dev

While in general I agree with you. I'd just like to mention one counter argument, which the rigidity of the code in some cases will help to protect against developers from using cheaper materials, or new materials that on paper seem better, but in reality may not be better. An example I've heard of but am having trouble searching for the exact name, is in condo buildings here in Canada they started using a new piping material, to do the water deliver inside the units. The problem was, while I think in theory the material was better, it has the property that when it fails it fails catastrophically, due to either a manufacturing or installation defect. So instead of just having a small pinhole leak, the piping will split when compromised, and you have many thousands of dollars in damages to multiple units. Buildings with this material can no longer be insured in Canada. So I don't know that I would really trust giving developers a wide latitude in selecting materials, even if they sound great on paper. I don't know what the solution is, because I agree we need to be more flexible, and have a way to introduce new and better technologies, but we also have to be diligent, in ensuring that the new technologies and processes work the way we expect them to, and have the desired effects.

3pt14159 10y ago
In Canada we use what is called limit states design and it handles the sudden failure vs gradual failure already. Essentially if you want to use a member or a material that suddenly fails you must design it to fail one tenth as often. In practice engineers go even more overboard because nobody wants blood on their hands and gradual failure greatly decreases the odds of that from happening. In terms of construction materials in condos failing (glass and piping) I actually put the blame for those two failures on the individual testing companies. Engineers in Canada don't understand statistics properly because most aren't taught materials testing properly in university. But we don't live in a utopia either. It is expected that things will go wrong sometimes and that we'll have to update our building codes to address those shortcomings. My issue with Canada is that we don't have a (or at least I'm not aware of there being a) structured materials testing code. Sure we'll regulate materials and connections for our main structural elements, but there will always be that last mile where someone will want to do something weird (like build part of the building under railway or if someone over bent some reinforcement bar and you need to authorize them rolling it back) and you're pretty much out on your own once you come to those scenarios. It's doubly unfortunate because most of the engineers that just look things up in tables are basically helpless because they don't remember or use the basics day-to-day. So they end up being extremely conservative - unnecessarily wasting money and material for all of us.
- abduhl 10y ago
  I don't practice in Canada, but my understanding was that the CSA is an analogue to the ASTM codes here in America (and internationally apparently, if you believe their name change). ASTM codes are very thorough when it comes to materials testing. I believe Europe has a similar standard. I don't understand how your third paragraph's thrust follows from your second paragraph - what does materials testing have to do with site specific (railway) or field changes (bent rebar)? How long did you practice in Canada? Your viewpoint of engineers meshes well with the opinion that I've heard from a lot of junior level engineers who are just making the adjustment to a mid-level position but are still interacting with the lower level staff who are, as you say, typically helpless. They are supposed to be - they are still learning.
  - 3pt14159 10y ago
    Only about 3 years before I got fed up and left. I'll fully admit I didn't get that involved with materials testing; and perhaps the firm I was with was substandard in this regard; but I don't think so. When I looked into the falling glass in Toronto I learned that they only tested a very small number of fasteners. I don't recall the number, but it was trivial statistics to prove that for the number of glass panes going up in Toronto they didn't have a large enough "n". The two examples I gave were two examples that I dealt with personally. I was extremely dismayed at the rigour the firm I was at used. To test the bent rebar I think we used a sample size of 6 and then tested to failure. For the railways example they just used the weight of the train. Then when I reviewed the designs and brought up that the train could apply the breaks and thereby increase the downward force they just multiplied everything by 2. In my experience the low level staff was useless, with a couple people that knew what they were doing. The medium level staff had two groups of people, the people that still knew advanced math and the people that got good at AutoCAD, and the senior people, while good at sales or general guidance; had basically completely forgotten all but the most basic structural engineering principles. I've literally had to explain crushing vs bending moment to a 20 year structural engineer before. I've (accidentally) designed a structure that was already designed by a senior person that forgot to put it in the tracking system. I used one sixth the steel and mine could handle more load. I will grant you, however, that I may have just been at a substandard firm. We had some large projects, but we weren't designing new skyscrapers or mega-structures.
WalterBright 10y ago
You're right, one reason engineers stay conservative is if the new ideas have problems that show up later, the engineer gets the blame. Hence he sticks with "nobody ever got fired for buying IBM". For example, when my house was built I wanted something better than fiberglas insulation. After research, I settled on icynene foam. The contractor refused to use it, because he'd be to blame if it went wrong, it would be an enormously expensive retrofit. He finally agreed after I formally agreed to accept the risk and not blame him. 15 years in, and the icynene has been great. No troubles at all.
- deleted 10y ago
  [deleted]

3pt14159 10y ago

In Canada we use what is called limit states design and it handles the sudden failure vs gradual failure already. Essentially if you want to use a member or a material that suddenly fails you must design it to fail one tenth as often. In practice engineers go even more overboard because nobody wants blood on their hands and gradual failure greatly decreases the odds of that from happening. In terms of construction materials in condos failing (glass and piping) I actually put the blame for those two failures on the individual testing companies. Engineers in Canada don't understand statistics properly because most aren't taught materials testing properly in university. But we don't live in a utopia either. It is expected that things will go wrong sometimes and that we'll have to update our building codes to address those shortcomings. My issue with Canada is that we don't have a (or at least I'm not aware of there being a) structured materials testing code. Sure we'll regulate materials and connections for our main structural elements, but there will always be that last mile where someone will want to do something weird (like build part of the building under railway or if someone over bent some reinforcement bar and you need to authorize them rolling it back) and you're pretty much out on your own once you come to those scenarios. It's doubly unfortunate because most of the engineers that just look things up in tables are basically helpless because they don't remember or use the basics day-to-day. So they end up being extremely conservative - unnecessarily wasting money and material for all of us.

abduhl 10y ago
I don't practice in Canada, but my understanding was that the CSA is an analogue to the ASTM codes here in America (and internationally apparently, if you believe their name change). ASTM codes are very thorough when it comes to materials testing. I believe Europe has a similar standard. I don't understand how your third paragraph's thrust follows from your second paragraph - what does materials testing have to do with site specific (railway) or field changes (bent rebar)? How long did you practice in Canada? Your viewpoint of engineers meshes well with the opinion that I've heard from a lot of junior level engineers who are just making the adjustment to a mid-level position but are still interacting with the lower level staff who are, as you say, typically helpless. They are supposed to be - they are still learning.
- 3pt14159 10y ago
  Only about 3 years before I got fed up and left. I'll fully admit I didn't get that involved with materials testing; and perhaps the firm I was with was substandard in this regard; but I don't think so. When I looked into the falling glass in Toronto I learned that they only tested a very small number of fasteners. I don't recall the number, but it was trivial statistics to prove that for the number of glass panes going up in Toronto they didn't have a large enough "n". The two examples I gave were two examples that I dealt with personally. I was extremely dismayed at the rigour the firm I was at used. To test the bent rebar I think we used a sample size of 6 and then tested to failure. For the railways example they just used the weight of the train. Then when I reviewed the designs and brought up that the train could apply the breaks and thereby increase the downward force they just multiplied everything by 2. In my experience the low level staff was useless, with a couple people that knew what they were doing. The medium level staff had two groups of people, the people that still knew advanced math and the people that got good at AutoCAD, and the senior people, while good at sales or general guidance; had basically completely forgotten all but the most basic structural engineering principles. I've literally had to explain crushing vs bending moment to a 20 year structural engineer before. I've (accidentally) designed a structure that was already designed by a senior person that forgot to put it in the tracking system. I used one sixth the steel and mine could handle more load. I will grant you, however, that I may have just been at a substandard firm. We had some large projects, but we weren't designing new skyscrapers or mega-structures.

WalterBright 10y ago

You're right, one reason engineers stay conservative is if the new ideas have problems that show up later, the engineer gets the blame. Hence he sticks with "nobody ever got fired for buying IBM". For example, when my house was built I wanted something better than fiberglas insulation. After research, I settled on icynene foam. The contractor refused to use it, because he'd be to blame if it went wrong, it would be an enormously expensive retrofit. He finally agreed after I formally agreed to accept the risk and not blame him. 15 years in, and the icynene has been great. No troubles at all.

deleted 10y ago
[deleted]