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Comment Re:Bridges Are Not Static Structures! (Score 2) 36

Maybe, but this won't catch a lot of failures caused by corrosion or fatigue cracking, or under-designed structures that are built with excessive static deflections from the get go. Many times the first excessive deflection is the one that sends the bridge into the river. Even if this worked as advertised, it does not replace visual inspection for defects.

Look at the I-35W bridge failure in Minnesota as a case in point. Sadly, this bridge *had* been inspected visually, numerous times, and was found to be structurally deficient by design, with cracking, corrosion, and bowed gusset plates all seen and photographically recorded prior to the collapse. It was cheaper to simply schedule periodic inspections, but the inspections never triggered the required (and costly) corrections that were needed. A peak load due to construction materials and gridlocked traffic was the last straw. All the GPS and satellites in the world can't cure human stupidity.

Comment Crack Filling = Hiding Critical Flaws? (Score 3, Insightful) 94

If the concrete fills it's own cracks automagically, two questions spring to mind: 1) Will the crack-filling material have the same load bearing properties or (as I suspect) it will be much weaker at those spots, and 2) will the filled cracks disguise the facts that the object may be under a load that was not anticipated by the designer (tensile or bending loads vs. compressive loads)?

Reinforced concrete is often used in bending and tensile load applications in architecture, and if the reinforcing is not stiff enough cracks often will appear on the surface. They are unsightly, but if the reinforcing is taking the load (as it should) these are not structural deficiencies. But for complex architectural domes and shells, the presence and size of these cracks is something that needs to be monitored.

If the concrete is used in a container and it cracks, we may actually want to see the crack as that is a warning that something is being loaded in an unanticipated way. Hiding it with a self-filling mechanism may not be desirable.

Comment Re:Snowden... (Score 1) 142

No, one can be pardoned even before being indicted. See Ford's pardon of Nixon for an example. The presidential pardon is a pretty powerful tool, but the president can't wield it too freely as there is great potential for political backlash against the party.

If a Republican gets the White House in 2016 (or even if they don't), I hope Obama mans up and pardons Snowden and Manning and others who blew the whistle on this. It would be one of the few things he could do to redeem his half-assed presidency IMO, but I am not holding my breath.

Comment If A Spy Agency Stops Collecting Data on You... (Score 2) 142

If a spy agency stops collecting data on you...how do you actually know?

Strangely enough, having a bunch of politicians say "We voted against it, so we won't collect data on you, promise!" really doesn't seem too compelling to me.

I think I will be keeping my tinfoil hat on with chin strap secured, thank you very much.

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