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London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

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31–40 of 58 posts

Re: London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

#31

Earlier quoted context omitted.

> Trust me, nobody will even remember a few years of delays. I remember someone commenting that given the choice, it's better to delay shipping video games if you need to fix things. This is because not long after release no one will remember it being late, but everyone will remember (hearing that) it being a pile of garbage. Reputations are often very hard to shake.

That's not true anymore with online updates and early access on steam. You can ship a game with lots of bugs and missing content, as long as the price is set in consequence.

I think there is only so far you can stretch that before reputational damage is too great. I've seen early access games effectively abandoned as result.

The soon to be classic example is cyberpunk. Funny this actually happened to them before with the first Witcher game, originally very buggy and had a re-release that patched it, but they were a smaller studio then and their reputation effectively unknown.

Re: London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

#32

Earlier quoted context omitted.

Who cares? These are rail lines which will be used for centuries. Trust me, nobody will even remember a few years of delays.

Well, in the context of the linked article and hence the comments here, it seems relevant to mention the fact - 5 years after the article's publication - and to consider whether the reliance on comprehensive digital modelling might be in any way to blame for the delays?

> consider whether the reliance on comprehensive digital modelling might be in any way to blame for the delays?

Maybe. 3D models have been used to design and plan projects for over 20 years now (I've been in the industry in Aus for >15 years), and so the bulk of the models are not at fault here (because if these design models were the delay, the construction would also be delayed, but the article suggests it wasn't). But when you want to go to the next level (digital twin), and start modelling every individual light-bulb, tracking it and making it function as part of a "smart system", then things will take a lot longer.

But actually, the article says;

> Despite the huge amount of construction work that has already been completed, many aspects of Crossrail do not yet have an agreed-upon final design. That’s because the complexity and uncertainty involved in building large underground structures means that detailed “fit out” designs are begun only after it’s fairly clear how the space will look.

This boggles my mind. I don't see how it couldn't all be completed at the start. The physical design should have a few flexibilities baked in, so that if the tunnel ends up a meter out of place, or the rail centerline is 200mm off target, the design should be able to absorb it with minimal re-work.

But regardless of the physical layout, they could have mocked up a model beforehand that contains all the necessary "virtual" components. They would have known what rooms/etc were required, roughly how many entities were needed per space (eg, 4 chairs, 1 table, all with data tags). Then when you have a better idea on the physical layout, you can arrange the virtual components properly.

So yes it's possible that trying to be too fancy was a major factor in the delays. I haven't worked in a professional software engineering environment, but I get the impression that at a high-level, construction engineering has similar traps and pitfalls. Just like when coding, engineers/modellers do come across problems with their initial design, and then have to face the choice of implementing significant work-arounds, or "refactor" to something different.

Re: London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

#33

Earlier quoted context omitted.

Who cares? These are rail lines which will be used for centuries. Trust me, nobody will even remember a few years of delays.

> "Who cares? ... nobody will even remember a few years of delays." If project timelines and budgets are not credible, it has very real implications for the viability of future infrastructure projects. It becomes much harder to justify future spending if you can't trust your models. Already (before than pandemic hit) the blow-outs on Crossrail were putting the north-south "Crossrail 2" line in doubt. Originally it wa…

Project timelines and budgets for projects of that size have never been predictable. Look at software development, the industry has largely moved away from trying to predict large projects and now just builds the smallest increments possible. Building infrastructure in a city with 100,000 unknowns underground is far worse.

Seattle had the same hand wringing around our newish rail line back in the early 2000s, now no one even knows it was late.

Also - Now that Seattle is around 85% vaccinated, offices are re-opening and the trains are full again. London is being more conservative in their approach to reopening, but they are merely months behind.

Re: London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

#34

Earlier quoted context omitted.

It isn't done yet... To really see how far the budget miss is, you have to wait for the thing to be finished and all costs accounted for, while also seeing how much the project has been scaled back (for example travel time goals not met because the trains are poorer performance than initially specced)

Class 345s were all manufactured and are already in service today. Is their performance in fact "poorer than initially specified" ?

I guess you'll see next year when the timetable is released

Re: London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

#37

Earlier quoted context omitted.

> "Who cares? ... nobody will even remember a few years of delays." If project timelines and budgets are not credible, it has very real implications for the viability of future infrastructure projects. It becomes much harder to justify future spending if you can't trust your models. Already (before than pandemic hit) the blow-outs on Crossrail were putting the north-south "Crossrail 2" line in doubt. Originally it wa…

Project timelines and budgets for projects of that size have never been predictable. Look at software development, the industry has largely moved away from trying to predict large projects and now just builds the smallest increments possible. Building infrastructure in a city with 100,000 unknowns underground is far worse. Seattle had the same hand wringing around our newish rail line back in the early 2000s, now no…

Trains are pretty full right now in London.

But just “full to capacity, standing room only” full, not ”full to beyond capacity, have to push and squeeze your way in before the doors close” like before the pandemic!

Re: London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

#38

Earlier quoted context omitted.

That's not true anymore with online updates and early access on steam. You can ship a game with lots of bugs and missing content, as long as the price is set in consequence.

I think there is only so far you can stretch that before reputational damage is too great. I've seen early access games effectively abandoned as result. The soon to be classic example is cyberpunk. Funny this actually happened to them before with the first Witcher game, originally very buggy and had a re-release that patched it, but they were a smaller studio then and their reputation effectively unknown.

You need to put that in context. Compared to a decade or two ago, an initial release was printed on DVD and unpatchable, a buggy game was effectively plastic waste. If it weren't bad enough, reviews and magazines would demolish it and make sure there were zero sales later on (not that there was a lot usually because most sales happened right after release).

It's an incredible progress for game developers that they can ship a buggy/incomplete game and improve it over the next year. (And you can write an announcement with every update to drive sales!)

Re: London’s Crossrail Is a $21B Test of Virtual Modeling (2016)

#40
post #32

Earlier quoted context omitted.

Well, in the context of the linked article and hence the comments here, it seems relevant to mention the fact - 5 years after the article's publication - and to consider whether the reliance on comprehensive digital modelling might be in any way to blame for the delays?

> consider whether the reliance on comprehensive digital modelling might be in any way to blame for the delays? Maybe. 3D models have been used to design and plan projects for over 20 years now (I've been in the industry in Aus for >15 years), and so the bulk of the models are not at fault here (because if these design models were the delay, the construction would also be delayed, but the article suggests it wasn't).…

A big issue with digging under London is that you never know what you'll find
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