What is the structural system of the Flatiron Building?

Detailed answer

The Flatiron Building's structural system is a steel frame, which was a innovative design feature at the time of the building's construction. The building's steel frame is composed of several interconnected columns and beams, which provide support for the building's floors and exterior walls. The steel frame is also designed to resist wind and seismic loads, and is anchored to the building's foundation through a system of deep foundations and footings. The building's structural system has been reinforced and upgraded over the years, and has been designed to meet modern seismic and wind load standards.