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The problem with reinforced concrete (2016)

theconversation.com

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Re: The problem with reinforced concrete (2016)

#3
This should be an economics piece, not an environmental piece. The author states that "one of iron’s unalterable properties is that it rusts" yet further on acknowledges the existence of stainless steel.

There's nothing wrong with reinforced concrete, but the incentives to produce long lasting buildings are not there. The cheapest bidder will generally win and their building will last the "design life" of the building, but often not much more. The simplest way to change this is to extend the design life, which would result in stainless steels or another more expensive material being used in this application.

Re: The problem with reinforced concrete (2016)

#4

This should be an economics piece, not an environmental piece. The author states that "one of iron’s unalterable properties is that it rusts" yet further on acknowledges the existence of stainless steel. There's nothing wrong with reinforced concrete, but the incentives to produce long lasting buildings are not there. The cheapest bidder will generally win and their building will last the "design life" of the buildin…

Is it a good thing for society to directly incentivize the construction of longer lasting buildings?

Re: The problem with reinforced concrete (2016)

#7
post #2

No mention of epoxy coatings for steel rebar? Look for green-coated rebar as you pass highway construction sites.

Epoxy coating is falling out of favour, as it has two downsides: 1) is has a weaker bond to the concrete, so you need longer bars to transfer the force, and 2) if it gets damaged (scratched or cut), the corrosion will concentrate at that location, and you are more likely to end up with a fully rusted-through bar, as opposed to a small amount of corrosion spread over the whole bar.

Reinforced concrete is much like clothing: a stitch in time saves nine. With regular cleaning and maintenance, it can last much longer than if you just let it deteriorate.

Re: The problem with reinforced concrete (2016)

#8
post #2

No mention of epoxy coatings for steel rebar? Look for green-coated rebar as you pass highway construction sites.

For some reason I stumbled across a wild YouTube channel by a guy named Tyler Ley that is “crazy for concrete”. If I remember correctly he’s a civil engineering professor and has a lot of fascinating videos about concrete.

In particular one about epoxy coated rebar that gives interesting notes about why it has its problems: https://youtu.be/xVDy84rR5Z8

I had a great couple of days learning all about the complexities of concrete through his videos.

Re: The problem with reinforced concrete (2016)

#10

This should be an economics piece, not an environmental piece. The author states that "one of iron’s unalterable properties is that it rusts" yet further on acknowledges the existence of stainless steel. There's nothing wrong with reinforced concrete, but the incentives to produce long lasting buildings are not there. The cheapest bidder will generally win and their building will last the "design life" of the buildin…

Is it a good thing for society to directly incentivize the construction of longer lasting buildings?

IMO yes; if the materials cost a lot of time/carbon/resources to produce, then we should make them last!
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