From coal to colossal

摘要

There are a few abandoned coal mines around Brownsville, Pa. Work also has stopped on the Monongahela River Bridge, but you can feel the energy in the air now more than ever. The deep valley of the Monongahela River required a bridge nearly 200 ft tall and a structure length of 3,000 ft. The high-strength piers, 30 ft by 23 ft, were created with 15-ft-tall jump forms that were advanced upward as the concrete lifts below were sufficiently cured.