Existing comment:
A Bathtub for the South Tower
To reach the site of the south tower foundation, workers constructed a temporary roadway on a timber access trestle, or wharf, from the San Francisco shore. The dangers of the exposed location soon became apparent in 1933, when a freighter collided with the trestle. Two months later, over half of the repaired structure collapsed in a storm. Undaunted, the engineers and workers restored the structure and continued their work.
The plans called for a huge oval-shaped concrete barrier, or fender, to protect the base of the south tower from ship collisions during fog. To build the fender, workers placed the concrete through tubes underwater into wood forms, where it set.
When the fender was built up above the water level and was visible, the workers called it a "giant bathtub." For the foundation pier, the base on which the tower would stand, workers placed concrete underwater to fill the bottom portion of the fender. After pumping out the remaining 9.4 million gallons (35.6 million liters) of seawater, workers inside the "bathtub" completed the placement of reinforcing steel and concrete.
Once the concrete work was done, the erection of the steel for the south tower began in January 1935 and was completed in just six months. |