One of the many marvels of engineering and safety on the Bridge Project is when the construction crews have to move really big things. Last week’s update showed the placing of the last cable stay pipe, where the crews moved a 540-foot pipe on and above the end span, then secured it to the tower and road deck. There, the challenge involved the length of the object being moved. In this week’s update, the challenges are weight and limited work space.
The video above shows the lifting and placement of one of the main span’s 116 140 foot-long floor beams near the closest columns on Terminal Island. These beams are about 6.5-feet high on the ends, rising to about 10 feet in the middle. They weigh 37 tons. Each floor beam attaches to the edge girders to create a grid of structural steel onto which the 16-foot by 30-foot concrete panels that will make up the road deck are placed.
Note in the video the tight fit between the already placed edge girders as the floor beam is lifted slightly above the road deck, then lowered into place. This movement must be performed very carefully to ensure proper safety and avoid damage to the previously placed steel or the beam itself. Toward the end of the video, note the proportional size of the construction worker on the edge girder, directing the lowering of the beam into place.