EDWARD'S LECTURE NOTES:
More notes at http://tanguay.info/learntracker
C O U R S E 
Roman Architecture
Diana Kleiner, Yale University
https://www.coursera.org/course/romanarchitecture
C O U R S E   L E C T U R E 
Opus Caementicum and Opus Incertum
Notes taken on January 23, 2014 by Edward Tanguay
concrete (Opus Caementicum [kigh-MENT-tee-kum]) changed the concept of architecture for the Romans
a shift from tradition architecture to innovative
tradition Roman architecture
Temple of Portunus
derivative that looked back at Greek and Etruscan religious architecture
Etruscan
tall podium
deep porch
single staircase
Greek elements
made of stone
Ionic order on columns
concrete
concrete was used already in the Temple of Portunus (1 BC), but only in the podium, you can't see it
can sustain great weights
placed in the podium for support
Romans at this time begin to see that concrete has an ability to transform Roman architecture
Roman concrete was different than today's concrete
composite of various natural elements that becomes a mass when mixed with water, and hardens into a very strong substance, much harder than any of its ingredients on its own
components
stone rubble
liquid mortar
lime, sand, and pozzolana, a volcanic substance
used in the early 2nd century BC
concrete is not cut or quarried, it is cast into molds
can be cast in any shape, at least any shape that a carpenter can build with wood
freed the Roman architect from the confines of a rectilinear architecture inherited from the Etruscans and the Greeks
greatest concrete structure: Pantheon
we can compare an Etruscan tomb which attempted to do the same thing, using stone
wasn't terribly successful, even had to put a stone column in the middle for support
two problems with concrete
has to be protected from moisture
is less attractive than stone
solved these two problems in the same way
when still wet, attached stone to it
large blocks or small rocks pressed into the concrete
Temple of Vesta at Tivoli
Opus incertum (uncertain masterwork) [in-KAIR-tum] protected the concrete with small stones
Sanctuary of Fortuna Primigenia at Palestrina
Palestrina is south of Tivoli
used a stone-facing Opus incertum
used often in the 2nd and 1st centuries BC
over time the choice of facing changed
under the Roman emperor Nerva, there was a revolution in Roman architecture
new facing material: brick
the attractiveness of brick