Research on self-healing concrete yields cost-effective system to extend life of structures
Efforts to extend the life of structures and reduce repair costs have led engineers to develop “smart materials” that have self-healing properties, but many of these new materials are difficult to commercialize. A new self-healing concrete developed and tested by a graduate student at the University of Rhode Island, however, may prove to be cost-effective. Michelle Pelletier, a URI master’s degree candidate from Woonsocket, embedded a microencapsulated sodium silicate healing agent directly into a concrete matrix. When tiny stress cracks begin to form in the concrete, the capsules rupture and release the healing agent into the adjacent areas.
Concrete for buildings has to be able to stand so much stress under prescribed building conditions. Though cracking is not uncommon. In a test between a concrete with the healing agent and without the one with the healing mixture recovered 26 percent of its original strength. They think if they tinker with the formula and proportions the recovery percentage could be improved. Since concrete manufacturing and repair are an intensive process which produces a lot of CO2 emissions, a self-healing mix which prolongs the life of concrete could substantially benefit the environment.
While David Brookes comes off as pretentious in his newest column Two Theories of Change – ( he usually does so why should this column be different) I’m grateful that he at least pays lip service to the Enlightenment and the philosophical concept of reason. Far more than we could expect from Newt Gingrich or Sarah Palin.
Their great model was Descartes. He aimed to begin human understanding anew. He’d discard the accumulated prejudices of the past and build from the ground up, erecting one logical certainty upon another.
What Descartes was doing for knowledge, others would do for politics: sweep away the old precedents and write new constitutions based on reason. This was the aim of the French Revolution.
But there wasn’t just one Enlightenment, headquartered in France. There was another, headquartered in Scotland and Britain and led by David Hume, Adam Smith and Edmund Burke. As Gertrude Himmelfarb wrote in her 2004 book, “The Roads to Modernity,” if the members of the French Enlightenment focused on the power of reason, members of the British Enlightenment emphasized its limits.
Descartes also deserves credit for trying, but his reasoning often did not distinguish between the real world and what he imagined,
Rene Descartes’ Ontological “Proof of God.” is, roughly:
1. I exist
2. I have in my mind the notion of a perfect being
3. An imperfect being, like myself, cannot think up the notion of a perfect being
4. Therefore the notion of a perfect being must have originated from the perfect being himself
5. A perfect being would not be perfect if it did not exist
6. Therefore a perfect being must exist
That perfect god would thus exist in all its perfection inside the head of every human being. That is obviously not the case. I can picture a perfect flying giraffe in my head, since I am not perfect, the perfect giraffe must be a concrete precursor of my thoughts? If that passes for logical certainty with Brookes and his followers I’m not surprised.
Brookes is probably pushing the boundaries of how The Enlightenment is usually defined when he says there was a British Enlightenment. There was a Scottish Enlightenment and included Hume (1711-1776). Smith, likewise was Scottish. Burke (1729-1797)was an Irishman who moved to England. Maybe the cutbacks at the NYT preclude his editor from taking time to check David’s columns. Excusable for an unpaid blogger, but not for a highly paid purveyor of conservative hackery. All this praising of reason is by way of Brookes presenting himself and his ideas as the moderate center to which we should all swoon forthwith. The center being that holy place from which so much of the best of humanity has arisen – like? “arrangements that had stood the test of time”. David is not one to be bothered with concrete examples. So we’re left to disagree on the pabulum he offers up as his general proof, The Cold Evasions
Understand that David Brooks has spent his entire adult life as the mouthpiece of one of the most radical and destructive movements in American history; and as his beloved Reagan Revolution Conservatism laid waste to the middle class…destroyed not merely America’s political comity, but the idea that political comity is a good thing...razed not merely the American federal government, but the idea that governance is a good thing…Bobo was there, cheering it on.
Cheering it on, and getting downright hysterical if anyone tried to pry the Gipper’s actual, ugly legacy out of the vice grip of his revisionist acolytes.
It was not until the blowback came — until the catastrophic and long-predicted consequences of his toxic and predatory ideology began washing unstoppably up on America’s shores — that Bobo suddenly discovered the Joys of Centrism, and started rifling through his yellowing undergraduate term papers and dropping them wholesale into the New York Times.
If Brookes is going to treat America, ideas and history with the elitism of a country club philosopher he should be expected to be treated with scorn in return.
Pvt. Joe Bowers: [addressing Congress] … And there was a time in this country, a long time ago, when reading wasn’t just for fags and neither was writing. People wrote books and movies, movies that had stories so you cared whose ass it was and why it was farting, and I believe that time can come again! – Idiocracy (2006)
inkbluesky 