There seems to be a rush to judgment to find the flaws that caused the I-35W bridge to collapse in Minneapolis. The new theory—faulty steel gusset plates—strikes me as grasping at straws. Why after 40 years would faulty plates suddenly result in a catastrophic failure? Why has this never been raised before as a potential flaw in this type of bridge? As MIT metallurgist Ken Russell pointed out here recently, steel is made in huge batches, and its chemistry is carefully tested. Suddenly we discovered that this ancient batch was a bad one? Or that the designer used a wrong gauge or grade of steel?
It probably will take months for a meaningful analysis of the bridge failure to emerge. Undoubtedly, the investigators will find a frightening list of contributors to the collapse, starting with the corroded steel roller bearings already reported as deficient in 1990.
The amount of plastic clogging the ocean continues to grow. Some startling, not-so-good news has come out recently about the roles plastic is playing in the ocean, as well as more heartening news about efforts to collect and reuse it.
Optomec's third America Makes project for metal 3D printing teams the LENS process company with GE Aviation, Lockheed, and other big aerospace names to develop guidelines for repairing high-value flight-critical Air Force components.
A self-propelled robot developed by a team of researchers headed by MIT promises to detect leaks quickly and accurately in gas pipelines, eliminating the likelihood of dangerous explosions. The robot may also be useful in water and petroleum pipe leak detection.
Aerojet Rocketdyne has built and successfully hot-fire tested an entire 3D-printed rocket engine. In other news, NASA's 3D-printed rocket engine injectors survived tests generating a record 20,000 pounds of thrust. Some performed equally well or better than welded parts.
Focus on Fundamentals consists of 45-minute on-line classes that cover a host of technologies. You learn without leaving the comfort of your desk. All classes are taught by subject-matter experts and all are archived. So if you can't attend live, attend at your convenience.