Sounds like it was built to correct engineering tolerances, but the tolerances caused too much wear on the carriages. Somebody reported the wrong number somewhere, and that’s what caused this.
Within tolerance is not, by definition, on target.
e.g. assume that the spec says 1200mm ± 4mm; running for 16km at 1196mm; this means that you are off target, whilst technically within spec it means that there is no margin on the negative side. Building at 1196mm effectively means your tolerance is -0+8mm which is very bad practice. A slightly thick rail takes you out of spec if measuring anywhere but the inside of the rail for placement.
I have worked with a lot of technical specs, some can be very specific about these kind of details.
When doing QC on a job, your goal is to hit target not just be within spec, questions should have been asked early as to why they were drifting off target, this is so you don’t get to the edge of your allowable range.
After WWII, to cater to a massively growing population, we as a nation (aka the government) spent between 10 - 15% of GDP on infrastructure (data from the Kaka podcast by Bernard Hickey); now we are spending somewhere between 5 - 10% of GDP on infrastructure.
So we used to spend roughly DOUBLE on infrastructure than we do today. We don’t necessarily suck at infrastructure, we just don’t invest like we used to.
Despite what National is trying to get you to believe, NZ is in a fairly good position WRT debt to GDP ratio. We could totally invest an extra 100 billion over 10 years to improve our infrastructure; it would basically double our ratio (current $83B to $395B or 21% in 2023 See: Stats NZ) this is “net debit” not sure what the difference is between net and total debit but I didn’t see a source for total debit (if there is a difference). Assuming the economy keeps growing at the 1.3% in this link the debit ratio would look something like $200B to $450B or 44%.
According to this we are already at 50.99%; I’m not sure how this relates to “net debit” on the stats NZ page.
The numbers are a bit vague, depending on source, the picture is pretty good, NZ is doing well internationally WRT debit to GDP ratio; we can afford major investment in infrastructure…unfortunately we would rather send billions overseas in interest payments to foreign banks by squeezing the housing supply thus jacking up the prices indefinitely.
This! So we under invest, and since the 80s have completely shat on public works and relied on private contracting & consulting to get things done.
Ideally we would reinstate the Ministry of Public Works and then slowly ramp up the spend on that $100B investment to give time to rebuild the experience and expertise that will eventually give us better value for the spend.
I read an article a few months ago, can’t find it now unfortunately, but it was arguing that making simple GDP comparisons between countries was getting harder as the purchasing power in different countries is so different. What we spend building a road vs Asian countries per km is kinda eye opening.
Maybe just small, remote country problems? A small country in Europe can draw on expertise from neighboring countries more easily than a small country in the South Pacific?
We used to have a public works that ensured we had a pool of expertise and then had a pipeline of projects always on the go to keep them in work. Now we do it all piecemeal, have no built in talent pool so have to contract & consult it all out.
I have no idea why this country sucks at infrastructure so much. Road are a mess, trains are a mess, ferries are a mess.
Sounds like it was built to correct engineering tolerances, but the tolerances caused too much wear on the carriages. Somebody reported the wrong number somewhere, and that’s what caused this.
Seems like a mistake they shouldn’t be able to make.
Agreed, it surprises me that this is able to happen.
I would assume that the bearers (sleepers) would be made in such a way as to locate the rails and keep the positioning at the optimum spacing.
Within tolerance is not, by definition, on target.
e.g. assume that the spec says 1200mm ± 4mm; running for 16km at 1196mm; this means that you are off target, whilst technically within spec it means that there is no margin on the negative side. Building at 1196mm effectively means your tolerance is -0+8mm which is very bad practice. A slightly thick rail takes you out of spec if measuring anywhere but the inside of the rail for placement.
That still means the spec is wrong, clearly.
That depends on what the spec says specifically.
I have worked with a lot of technical specs, some can be very specific about these kind of details.
When doing QC on a job, your goal is to hit target not just be within spec, questions should have been asked early as to why they were drifting off target, this is so you don’t get to the edge of your allowable range.
If the spec can be followed exactly and yield a bad result, the spec is fundamentally incorrect. (Even if that’s the usual way of doing things.)
how hard could be to fix that?
After WWII, to cater to a massively growing population, we as a nation (aka the government) spent between 10 - 15% of GDP on infrastructure (data from the Kaka podcast by Bernard Hickey); now we are spending somewhere between 5 - 10% of GDP on infrastructure.
So we used to spend roughly DOUBLE on infrastructure than we do today. We don’t necessarily suck at infrastructure, we just don’t invest like we used to.
Despite what National is trying to get you to believe, NZ is in a fairly good position WRT debt to GDP ratio. We could totally invest an extra 100 billion over 10 years to improve our infrastructure; it would basically double our ratio (current $83B to $395B or 21% in 2023 See: Stats NZ) this is “net debit” not sure what the difference is between net and total debit but I didn’t see a source for total debit (if there is a difference). Assuming the economy keeps growing at the 1.3% in this link the debit ratio would look something like $200B to $450B or 44%.
According to this we are already at 50.99%; I’m not sure how this relates to “net debit” on the stats NZ page.
The numbers are a bit vague, depending on source, the picture is pretty good, NZ is doing well internationally WRT debit to GDP ratio; we can afford major investment in infrastructure…unfortunately we would rather send billions overseas in interest payments to foreign banks by squeezing the housing supply thus jacking up the prices indefinitely.
This! So we under invest, and since the 80s have completely shat on public works and relied on private contracting & consulting to get things done.
Ideally we would reinstate the Ministry of Public Works and then slowly ramp up the spend on that $100B investment to give time to rebuild the experience and expertise that will eventually give us better value for the spend.
I read an article a few months ago, can’t find it now unfortunately, but it was arguing that making simple GDP comparisons between countries was getting harder as the purchasing power in different countries is so different. What we spend building a road vs Asian countries per km is kinda eye opening.
Maybe just small, remote country problems? A small country in Europe can draw on expertise from neighboring countries more easily than a small country in the South Pacific?
We used to have a public works that ensured we had a pool of expertise and then had a pipeline of projects always on the go to keep them in work. Now we do it all piecemeal, have no built in talent pool so have to contract & consult it all out.