R3d M3rcury writes with the story that "NASA and Boeing, along with other nations, are studying the feasibility of keeping the International Space Station in orbit until 2020
and possibly until 2028 — the 30 year anniversary of the launch of the first module." From the article: "To assess the long-term structural health of the station, Boeing engineers developed detailed computer models based on NASA's projected use -- the expected stresses caused by future dockings, reboosts, crew activity and thermal cycles -- and combined that with actual data from on-board accelerometers and strain gauges. ... "What we're looking at is theoretical crack growth," Pamela McVeigh, the engineer in charge of the Boeing structural analysis in Houston, told CBS News. "So the failure mode would be you'd have a crack beginning, probably (at) a bolt hole, and the crack would grow to another edge. So you'd lose like a flange on a C-beam, or an I-beam. The stiffness of your structure would then change, the bolt hole you that you were growing the crack out of, now that bolt wouldn't be effective."