This August 6 & 9 (2015) marks the 70th Anniversary of the dropping of the Atomic Bombs on Hiroshima & Nagasaki. Coming across two images showing damage after the bombing in this collection really gave me something to think about. As I have always thought of the human cost of the bombings, looking at it from a structural, building perspective was a new and interesting perspective for me.
From an engineering and architectural perspective, there was a lot to learn from in the piles of rubble left by “Little Boy” and “Fat Man.” The “Little Boy” bomb, dropped over Hiroshima, exploded approximately 1,900 feet from the ground, the immediate concussion destroying almost everything within 2 miles of ground zero. “Fat Man”, dropped over Nagasaki, exploded approximately 1,500 feet from the ground, producing blast forces that traveled over 9,000 mph and damaged buildings over 3 miles from the epicenter. One third of the entire city was completely destroyed. People and buildings near the explosions were vaporized. After the explosions, some partial structures remained. The blasts produced heat greater than 7,000 degrees F at ground level. Buildings not destroyed by the concussion of the explosion were incinerated.
The impact of an atomic bomb is felt in many ways– a giant shockwave, wind speeds greater than a tornado, and immense heat, as well as radiation and other non-immediate effects. The damage these bombs caused was immense and unprecedented. Hundreds of thousands of people were killed and tens of thousands of buildings were destroyed. The only structures to survive in the blast area were those built to resist earthquakes.
In this collection, there were images showing the damage done to reinforced concrete buildings near the explosions that were meant to withstand the impact of earthquakes.
This photograph is of a building just a few hundred feet from the epicenter of the Hiroshima explosion.
This is a view from inside a factory near ground zero in Nagasaki, showing a close up view of the destruction to the beams and columns of the building. Both of these images are courtesy of the US Department of Energy (Glasstone, 1964).
By Tim Morgan