I was sure those ancient Roman concrete recipes were just myths until I saw a harbor pier in Italy still standing after 2,000 years

A marine archaeologist at the Bay of Naples showed me the chemical analysis proving their lime and volcanic ash mix actually gets stronger over time in seawater, and now I'm wondering how many other old building tricks we've been ignoring.

2 comments

2 Comments

kim.dylan1mo ago

You know what REALLY gets me about this is the specific ratio they used - 1 part lime to 3 parts volcanic ash with those chunks of aggregate mixed in. I read that the lime particles actually dissolve and recrystallize in the seawater, filling in any cracks that form. Makes me wonder how much of our modern concrete problems come from us being too cheap with the right materials. Have you looked into whether any labs have tried to reproduce that exact mix and test it against modern Portland cement? Because I'd bet money the roman stuff outperforms it in marine environments.

the_kim1mo ago

Wait hold on, that whole thing about the lime particles dissolving and then RECRYSTALLIZING in seawater to fill cracks? That's insane. I thought I knew the basics but I never heard that part before. So basically the concrete heals itself like some kind of sci-fi material while our modern stuff just crumbles.