It is one of the largest cathedrals in the world, and it was built in record time. An ancient and monumental structure that survived fires, earthquakes, and riots: The Hagia Sophia Museum. The construction began in February, 532 and it was intended to be the largest cathedral in the Byzantine Empire. Emperor Justinian 1 gave the task to the physicist Isidore of Miletus and Anthemius. Their design was quite challenging. 4 grand arches, galleries, and a gorgeous dome 56 meters high.
In order to create the largest main ground, four massive piers connected by 4 arches which are 31 meters in width were built. But this way, the dome would sit only on the highest points of the arches and arches wouldn’t be able to carry the dome. That’s why in order to set a circular dome on a square base, four curved structures shaped like curved triangles were made. This way both the dome would sit tightly on the arches and the lateral pressure of the arches would be restrained. And yet, Isidore and Anthemius had a bigger problem lying ahead of them. How would the piers be able to carry the weight of a dome 31 meters in diameter and 56 meters in height?
First, lighter material would have to be preferred. The bricks used in Hagia Sophia are different from the usual ones. Since they were baked at low temperature, they have a porous texture, therefore, are lighter. Besides, the mortar used in laying the bricks was made of crushed bricks. Because they were both made of the same material, mortar adhered to brick firmly once when it got dry. Anyway. Why hasn’t Hagia Sophia collapsed for 1500 years? How has it survived dozens of earthquakes? The weight of the dome remained a problem. As a last resort, a series of half-domes were built under the main dome.
Despite the measures taken, the piers wouldn’t do a good job in carrying the huge dome. Even today, you can see how the weight of the dome has tilted some columns outward. The worst fears were to be realized in an earthquake in 557, 20 years after the construction, and the main dome collapsed. This time, it was Isidore the Younger, a nephew of the physicist Isidore, who would repair it. He came up with a brilliant solution. He abandoned the old shallow dome and built an almost hemisphere instead. Maybe it was not a perfect hemisphere, but it has survived for 1500 years.
And yet, if it weren’t for the last additions, the structure would have collapsed anyway. Lastly, the architect Sinan built the exterior buttresses. Despite all its deficiencies, it’s not wrong to say Hagia Sophia was designed to be earthquake-resistant. The 40 windows at the dome’s base against a crack, and the iron rings on the top and the base of the columns are the proof of it. With the 4 minarets added after the conquest of Istanbul, the structure took its final form and it seems that it will survive for many more years to come.