Why is it called a pentagonal design?

Pentagon. Construction workers on the Pentagon site in November 1941. At the beginning of 1941, Hitler took control of most of Europe, and Roosevelt, then the United States, declared a national emergency.

The burgeoning U.S. War Department (which existed from 1789 to 1947) was in dire need of a new command base, and the Pentagon began construction.

The Pentagon is poorly grounded, originally a large uninhabited swamp near the river. To do this, construction workers laid 41,492 cement pillars and dug 680,000 tons of sand and gravel from the nearby Potuo Marco River to press 300,000 cubic meters of reinforced concrete building materials. The Pentagon's design saved steel for the war years to build a battleship.

It has a total floor area of 29 acres, which is equivalent to five U.S. Congresses.

The Pentagon's design chief was Brigadier General Brian Burke Summerville. When he was tasked with the task, he had only four days to submit a design for an administrative building with fire protection and full air conditioning that could accommodate 40,000 people. Somerville was known for his harshness, and his collaborators later commented on him

He's like dynamite in a jar." Somerville was a strong advocate of moving the U.S. Department of War from Washington to Arlington-on-Tomac.

This is the original design drawing of the Pentagon, which at the time was also designed as an irregular pentagon. Based on the available land area and the limitations of the building shape (square or rectangular footprint is too large), the pentagonal shape was considered the best architectural shape for the building.

In July 1941, the Pentagon's three-dimensional architectural drawings were successfully drawn. Although its irregular shape still raises many problems, the design of the pentagonal shape is still the best choice due to the constraints of the objective environment. The cartographer Socrates Thomas later recalled:

Pentagon) is best suited for it. ”

In January 1943, just 16 months later, the world's largest office building was completed, and the Pentagon, named after its shape, was immediately put into use, playing an important military command function in the latter part of World War II.

In September 1947, the Department of Defense established by the 33rd Truman of the United States began to work here. Since then, the Pentagon has become a synonym for the US Department of Defense.

According to the final count, the Pentagon, which cost $87 million, has a total of miles (about 28 kilometers) of corridors, 7,754 windows, and is 71 feet and inches (about 22 meters) high.

On May 12, 1993, the U.S. Department of the Interior designated the Pentagon as a National Historic Symbol.