In the same vain I just noticed this comment I made days ago never got onto the board, no surprise, it’s gotten to be insane with interruptions around here.
Guess that might work chemically, although seems more a matter of serendipity (what are we going to do with all these bodies?) rather than being puzzled out by some structural chemist. Sort of like the Romans were simply lucky that it’s the kind of raw material they had available.
Might I suggest keeping Galveston, Texas off your vacation bucket list. 
I read a fascinating book Isaac’s Storm by Erik Larson a few different stories that unfold together with the monster hurricane of 1900 - it includes a rather macabre postscript.
Life is harsh, the dead are buried and the living move on.
Ironically web surfing about flexible glass, (not to be mistaken with glass that will bend), brought me back to concrete and yet more layers of details to the solution of the Roman concrete mystery. Beyond the whole availability of occasional soluble calcium, dealing with salt intrusion seems every bit as important. Folds within fold of complexity. 
The composition of Roman concrete has been long known, being a mixture of volcanic ash, quicklime (calcium oxide) and volcanic rock, but the science behind its resilience to seawater remained unknown until recently. It is thought volcanic material was used after the Romans observed ash from volcanic eruptions crystallize to form durable rock.
The research team discovered that while modern concrete is made to be inert, the Roman version interacts with the environment.
When seawater interacts with the mixture, it forms rare minerals aluminous tobermorite and phillipsite which are believed to strengthen the material. This discovery could lead to the development of more resilient concrete to be used in coastal environments. …
Roman concrete however does not appear susceptible to any of these processes. The research team found that seawater, the kryptonite to modern concrete, was the magic ingredient responsible for the structural stability of the Roman mixture. The Roman concrete samples were found to contain rare aluminous tobermorite and phillipsite crystals. It is believed that with long-term exposure to seawater, tobermorite crystalizes from the phillipsiteas it becomes more alkaline.
This crystallization is thought to strengthen the compound, as tobermorite has long plate-like crystals that allow the material to bend rather than crack under stress. Pliny the Elder in the first century CE exclaimed “that as soon as it [concrete] comes into contact with the waves of the sea and is submerged [it] becomes a single stone mass (fierem unum lapidem), impregnable to the waves and every day stronger.”
'To arrive at these conclusions, Jackson et. al. (2017) performed scanning electron microscopy (SEM), micro x-ray diffraction (XRD), Raman spectroscopy and electron probe microanalysis at the Advanced Light Source at the Lawrence Berkeley National Laboratory. …"
Why do people bomb the hell out of cities with alacrity? … and always feeling self-justified doing it?
Why do we continue destroying our global life support system with wanton abandon?
Why are we humans so incapable of recognizing our monster side?
