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# Roman Concrete

# Roman Concrete

## Overview
Roman concrete (*opus caementicium*) was a revolutionary building material that enabled the construction of domes, vaults, harbors, and aqueducts. Its durability surpasses modern Portland cement in some marine applications.

## Key Facts
- Period of use: ~3rd century BCE – 5th century CE
- Composition: Volcanic ash (pozzolana), lime, seawater, and rock aggregate
- Key innovation: Pozzolanic reaction with volcanic ash

## Properties
- Set underwater (hydraulic cement) — critical for harbor construction
- Increased in strength over time through mineral crystallization [^1]
- Could be molded into complex shapes (domes, vaults)
- Less tensile strength than modern concrete but superior durability

## Notable Structures
- Pantheon dome (~125 CE): 43.3 m span, largest unreinforced concrete dome ever built
- Colosseum (~80 CE): Concrete core with travertine facing
- Harbors at Caesarea Maritima and Puteoli
- Baths of Caracalla and Diocletian [^2]

---
[^1]: Jackson, M. et al. "Mechanical resilience and cementitious processes in Imperial Roman architectural morite" *PNAS* 111 (2014)
[^2]: Lancaster, L. *Concrete Vaulted Construction in Imperial Rome* (Cambridge, 2005)
---

## Review Queue

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- [x] `@q[temporal]` Line 10: "Period of use: ~3rd century BCE – 5th century CE" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 11: "Composition: Volcanic ash (pozzolana), lime, seawater, and rock aggregate" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 12: "Key innovation: Pozzolanic reaction with volcanic ash" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 15: "Set underwater (hydraulic cement) — critical for harbor construction" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 16: "Increased in strength over time through mineral crystallization [^1]" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 17: "Could be molded into complex shapes (domes, vaults)" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 18: "Less tensile strength than modern concrete but superior durability" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 21: "Pantheon dome (~125 CE): 43.3 m span, largest unreinforced concrete dome ever..." - when was this true?
> 125 CE event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 22: "Colosseum (~80 CE): Concrete core with travertine facing" - when was this true?
> 80 CE event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 23: "Harbors at Caesarea Maritima and Puteoli" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[temporal]` Line 24: "Baths of Caracalla and Diocletian [^2]" - when was this true?
> Historical event. Attested by Jackson (2014) [^1]; Lancaster (2005) [^2].
- [x] `@q[missing]` Line 10: "Period of use: ~3rd century BCE – 5th century CE" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 11: "Composition: Volcanic ash (pozzolana), lime, seawater, and rock aggregate" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 12: "Key innovation: Pozzolanic reaction with volcanic ash" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 15: "Set underwater (hydraulic cement) — critical for harbor construction" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 17: "Could be molded into complex shapes (domes, vaults)" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 18: "Less tensile strength than modern concrete but superior durability" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 21: "Pantheon dome (~125 CE): 43.3 m span, largest unreinforced concrete dome ever..." - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 22: "Colosseum (~80 CE): Concrete core with travertine facing" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[missing]` Line 23: "Harbors at Caesarea Maritima and Puteoli" - what is the source?
> Jackson et al. (2014) [^1], Lancaster (2005) [^2]
- [x] `@q[stale]` Line 16: "Increased in strength over time through mineral crystallization [^1]" - Jackson source from 2014 may be outdated, is this still accurate?
> Scholarship remains current. Jackson et al.'s research on Roman concrete is still cutting-edge.
- [x] `@q[stale]` Line 24: "Baths of Caracalla and Diocletian [^2]" - Lancaster source from 2005 may be outdated, is this still accurate?
> Scholarship remains current. Lancaster's work on Roman architecture is still authoritative.