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Decades of civil engineering differs with you. The cost to move a cubic yard of soil is rather well known for a given area. Labor costs are well established. I

Decades of civil engineering differs with you. The cost to move a cubic yard of soil is rather well known for a given area. Labor costs are well established. I don't see how he is going to cut enough corners to make it cheaper by any noticeable amount. Privately funded earthwork projects are nothing new.

natosaichek 8y ago
>The cost to move a cubic yard of soil is rather well known for a given area Given traditional technologies and techniques > Labor costs are well established Primarily for union labor using traditional tools and techniques. When spacex was started, the cost to move a kg of satellite into low earth orbit was well known. The cost of a new rocket development program from an engineering hours / labor cost perspective was also well established. He broke a few assumptions people had, which resulted in dramatically lower costs. I don't see why that strategy wouldn't _fundamentally_ play out similarly for TBC.
- jcranmer 8y ago
  > I don't see why that strategy wouldn't _fundamentally_ play out similarly for TBC. Because they have given a reason why they expect lower costs. They don't expect to be able to actually reduce the cost of a boring a tunnel at fixed diameter; they want to bore smaller tunnels and assert that's good enough.
- takk309 8y ago
  Traditional technologies and techniques for earth moving are rather simple and well refined. Moving soil still requires one to excavate the soil and transport the soil. I can't see any way around that. There are only so many ways to improve on this model. In rural environments it is possible to use larger haul trucks to move the materials. The urban nature of the construction site will limit the size of vehicles that can be used to transport the materials. As for the excavation equipment, a tunnel boring machine (TBM) is obviously the tool of choice. Maybe some efficiencies can be gained with the TBM through some sort of re-usability. The space analogy, in mind, is not a great one. Prior to SpaceX, launches were generally a rare and expensive thing. Musk has changed that by making the process more efficient. Earth work, on the other hand, is done every day. There is likely a large dirt moving operation somewhere near every person that will see this thread. Be it excavation for the foundation of a large building or the construction of a roadway, moving earth is extremely common. [edit] Clarity in the last sentence of the first paragraph.

natosaichek 8y ago

>The cost to move a cubic yard of soil is rather well known for a given area Given traditional technologies and techniques > Labor costs are well established Primarily for union labor using traditional tools and techniques. When spacex was started, the cost to move a kg of satellite into low earth orbit was well known. The cost of a new rocket development program from an engineering hours / labor cost perspective was also well established. He broke a few assumptions people had, which resulted in dramatically lower costs. I don't see why that strategy wouldn't _fundamentally_ play out similarly for TBC.

jcranmer 8y ago
> I don't see why that strategy wouldn't _fundamentally_ play out similarly for TBC. Because they have given a reason why they expect lower costs. They don't expect to be able to actually reduce the cost of a boring a tunnel at fixed diameter; they want to bore smaller tunnels and assert that's good enough.
takk309 8y ago
Traditional technologies and techniques for earth moving are rather simple and well refined. Moving soil still requires one to excavate the soil and transport the soil. I can't see any way around that. There are only so many ways to improve on this model. In rural environments it is possible to use larger haul trucks to move the materials. The urban nature of the construction site will limit the size of vehicles that can be used to transport the materials. As for the excavation equipment, a tunnel boring machine (TBM) is obviously the tool of choice. Maybe some efficiencies can be gained with the TBM through some sort of re-usability. The space analogy, in mind, is not a great one. Prior to SpaceX, launches were generally a rare and expensive thing. Musk has changed that by making the process more efficient. Earth work, on the other hand, is done every day. There is likely a large dirt moving operation somewhere near every person that will see this thread. Be it excavation for the foundation of a large building or the construction of a roadway, moving earth is extremely common. [edit] Clarity in the last sentence of the first paragraph.