for - quote - sustainable building - concrete paradox

quote - sustainable building - concrete paradox - It does not make sense today to: - quarry limestone, - burn it with aluminium and a few other ingredients at extremely high temperatures to create a powder that is - mixed with - water, - sand and - gravel - to convert it back into a solid material. - And concrete is not good in tension. - It has to be reinforced with steel in order to build with it.