3 ms·
Could you have an outer tube with concrete and expansion joints, then a membrane on the inside that maintains smoothness but expands/contracts as the tube moves
by wastedhours 10y ago
Could you have an outer tube with concrete and expansion joints, then a membrane on the inside that maintains smoothness but expands/contracts as the tube moves?
- lisper 10y agoWhat would the membrane be made out of? Remember, it's not enough to be smooth. You have to be: 1. Smooth (on the inside) and 2. Straight and 3. Strong (enough to bear the stress of having a multi-ton vehicle passing within a few millimeters at 700MPH) and 4. Long (300 miles at least) and 5. Airtight for that entire length, and 6. Cost-effective. It is that combination of features that no one has ben able to even begin to tell a story about how they would make it work in the face of thermal expansion.