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Bacteria and sand engineered into living concrete

eurekalert.org

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Re: Bacteria and sand engineered into living concrete

#11

Post by feintruled »

This reminds me of the JG Ballard story Venus Smiles, which I found whimsical and scientifically ridiculous at the time of reading, where an artist creates a living sculpture which basically makes a hell of a racket and grows itself out of control. Panicking, the owner has it cut up and sold for scrap, only to start hearing the same noises start when he is in new buildings - the tainted metal has been used in construction projects from the melted down scrap and is proliferating - "The whole world will be singing."!

Reading this news story it seems that one could retrofit a bacteria based scientific explanation - perhaps not so outlandish after all. What an amazing futurist he was!

https://en.wikipedia.org/wiki/Venus_Smiles

Re: Bacteria and sand engineered into living concrete

#12

Post by jbotz »

frandroid wrote: post #6

We already have slow-curing low-emissions concrete, which has existed for centuries. Fast setting is a core feature of modern (Portland) concrete, and any "replacement" which doesn't do that is not a replacement at all. Companies want to build their 40-story towers in 6 months, not 6 years.

A lot of concrete is used for making standardized "pre-molded" parts (blocks, panels, structural elements) and those can absolutely by made using a much slower process, stocked and then rapidly assembled during construction.

Re: Bacteria and sand engineered into living concrete

#13

Post by jbotz »

frandroid wrote: post #6

We already have slow-curing low-emissions concrete, which has existed for centuries. Fast setting is a core feature of modern (Portland) concrete, and any "replacement" which doesn't do that is not a replacement at all. Companies want to build their 40-story towers in 6 months, not 6 years.

Our modern concrete has not existed for "centuries"... Portland cement was invented about 150 years ago, and steel-reinforced concrete started being used just over 100 years ago.

Re: Bacteria and sand engineered into living concrete

#14

Post by jbotz »

Ericson2314 wrote: post #2

Can it use desert sand rather than riverbed sand?

All sorts of stuff can be used for agregate, but not all of it produces concerte of the same quality. Also, the problem is local availability... most of the sheer mass of our construction projects is the aggregate for the concrete, so getting the aggregate from a distant source would be almost like constructing the whole building there and then transporting it to its final location!

There is essentially an endless supply of aggregate on this planet, it's the transportation costs that are prohibitive (both in terms of money and of course the environmental costs of transportation).

Re: Bacteria and sand engineered into living concrete

#16

Post by agumonkey »

jbotz wrote: post #12
frandroid wrote: post #6

We already have slow-curing low-emissions concrete, which has existed for centuries. Fast setting is a core feature of modern (Portland) concrete, and any "replacement" which doesn't do that is not a replacement at all. Companies want to build their 40-story towers in 6 months, not 6 years.

A lot of concrete is used for making standardized "pre-molded" parts (blocks, panels, structural elements) and those can absolutely by made using a much slower process, stocked and then rapidly assembled during construction.

I'm often dumbfounded when I see building with cast cement only to be broken down with cranes later. Is it stupid (unstable) to make cement blocks and build by stacking most of them (maybe keep pillars and floors cast). So you can reuse them.

Re: Bacteria and sand engineered into living concrete

#17

Post by [deleted] »

jbotz wrote: post #13
frandroid wrote: post #6

We already have slow-curing low-emissions concrete, which has existed for centuries. Fast setting is a core feature of modern (Portland) concrete, and any "replacement" which doesn't do that is not a replacement at all. Companies want to build their 40-story towers in 6 months, not 6 years.

Our modern concrete has not existed for "centuries"... Portland cement was invented about 150 years ago, and steel-reinforced concrete started being used just over 100 years ago.

[deleted]

Re: Bacteria and sand engineered into living concrete

#18

Post by frandroid »

jbotz wrote: post #13
frandroid wrote: post #6

We already have slow-curing low-emissions concrete, which has existed for centuries. Fast setting is a core feature of modern (Portland) concrete, and any "replacement" which doesn't do that is not a replacement at all. Companies want to build their 40-story towers in 6 months, not 6 years.

Our modern concrete has not existed for "centuries"... Portland cement was invented about 150 years ago, and steel-reinforced concrete started being used just over 100 years ago.

I'm talking about lime-based cement, which predates Portland cement and steel-reinforced concrete. Portland cement is a huge source of CO2 emissions.

Re: Bacteria and sand engineered into living concrete

#19

Post by Psyladine »

agumonkey wrote: post #16
jbotz wrote: post #12

Earlier quoted context omitted.

A lot of concrete is used for making standardized "pre-molded" parts (blocks, panels, structural elements) and those can absolutely by made using a much slower process, stocked and then rapidly assembled during construction.

I'm often dumbfounded when I see building with cast cement only to be broken down with cranes later. Is it stupid (unstable) to make cement blocks and build by stacking most of them (maybe keep pillars and floors cast). So you can reuse them.

As a counter, do you want to buy a brand new Tesla made with "100% recycled parts from former cars!"?

Re: Bacteria and sand engineered into living concrete

#20

Post by blackearl »

Psyladine wrote: post #19
agumonkey wrote: post #16

Earlier quoted context omitted.

I'm often dumbfounded when I see building with cast cement only to be broken down with cranes later. Is it stupid (unstable) to make cement blocks and build by stacking most of them (maybe keep pillars and floors cast). So you can reuse them.

As a counter, do you want to buy a brand new Tesla made with "100% recycled parts from former cars!"?

I'd buy a refurb at a refurb price. My car is 10 years old and still running great so I can't imagine a refurbished newer vehicle running any worse.
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