architecture

1. Florence cathedral
•
• Cathedral of santa maria
• By the beginning of the fifteenth century, after a hundred years of construction,
the structure was still missing its dome. The basic features of the dome had been
designed by Arnolfo di Cambio in 1296.

2. Early Renaissance Architecture • 1400-1500
Filippo Brunelleschi, the first great architect of the Renaissance, worked primarily in
churches. His most famous masterpiece is the octagonal brick dome he designed
for Florence Basilica (an Italian Gothic church), an engineering feat of such
difficulty (due to the dome's unprecedented size) that he also had to invent special
machines to hoist each section into place.

3. This dome is the most famous transitional work between Medieval and
Renaissance architecture
. Although at first glance it appears to be very much a Gothic dome (given its
pointed shape and ribbed frame)5, it is considered a transitional work due to
Brunelleschi's attention to balanced proportions and simple decoration. It is
crowned by a lantern, a rooftop structure with openings for lighting or
ventilation.

4. Dome of florence cathedral
Is an octagonal dome higher and wider than any that had
ever been built, with no external buttresses to keep it from
spreading and falling under its own weight.
The drum or base of the dome was already in place before
Brunelleschi received the assignment to complete it.
The span of the octagonal drum was 140 feet, a very large
span for a dome at that time, especially one without the
possibility of external buttressing or supports.
Brunelleschi knew that a hemispheric dome (one which
is perfectly rounded) would not be able to span this
distance without the use of external buttresses.
As a result, he decided to make a pointed dome. He placed
8 major ribs at the points of the octagon, and 16 minor ribs
(two in the space between every two major ribs), all tied
together by lateral bands.
.

5. – The dome was double-shelled (the first one, in fact), with brick near the top,
rather than stone, laid in horizontal courses one row at a time, which meant that
each row carried the weight of the next one. This was an ingenious solution
because each row became part of the scaffolding.
– The spreading problem was solved by a set of four internal horizontal stone and
iron chains, serving as barrel hoops, embedded within the inner dome: one each
at the top and bottom, with the remaining two evenly spaced between them. A
fifth chain, made of wood, was placed between the first and second of the stone
chains. Since the dome was octagonal rather than round, a simple chain,
squeezing the dome like a barrel hoop, would have put all its pressure on the
eight corners of the dome. The chains needed to be rigid octagons, stiff enough to
hold their shape, so as not to deform the dome as they held it together.
To lift 37,000 tons of material, including over 4 million bricks, he invented hoisting
machines and lewissons for hoisting large stones. These specially designed
machines and his structural innovations were Brunelleschi's chief contribution to
architecture.

6. The lantern was finally completed by Brunelleschi's friend Michelozzo in
1461. The conical roof was crowned with a gilt copper ball and cross,
containing holy relics, by Verrocchio in 1469. This brings the total height of
the dome and lantern to 114.5 metres (375 ft).

7. Brunelleschi’s design features a double-walled ovoid shell anchored at the
bottom by a 15 meter high tambour eliminating the need for scaffolding and
reinforcement. The dome is 44 meters in diameter and 113 meters high
topped by a lantern that is accessed by a stairway between the interior and
exterior walls of the dome. Florence Cathedral is commonly known simply
as The Duomo because of the beauty and magnificence of Brunelleschi's
design and its striking impact on the skyline of Florence

8. • A huge statue of
Brunelleschi now sits
outside the Palazzo dei
Canonici in the Piazza del
Duomo, looking
thoughtfully up towards his
greatest achievement, the
dome that would forever
dominate the panorama of
Florence. It is still the
largest masonry dome in
the world.