Why hasn't the Pantheon's dome collapsed?

Summary by Krater

This video examines how ancient Roman architects built the Pantheon in Rome, detailing its construction techniques, use of concrete, and structural engineering solutions designed to support its massive unreinforced concrete dome.

From the video

Answers: How was the Pantheon built?

• Roman concrete construction
• Pantheon architecture and engineering
• Dome structural mechanics
• Ancient building materials and quarries
• Portico design and columns

What it concludes

• The Pantheon's rotunda interior diameter and interior height are both exactly 150 Roman feet.
• Most laborers working on the Pantheon were freemen, while some master craftsmen were slaves.
• The Pantheon's foundation was made of concrete, forming a ring 7.3 meters wide and at least 7 meters deep.
• The rotunda walls were engineered with varying thickness and lightweight volcanic scoria aggregates in the upper dome to counteract hoop stress and downward weight.
• The Pantheon's monolithic columns are made of Egyptian granite shipped from Aswan and Mons Claudianus.