Pat Shingleton: "Dams and Concrete"
On this date, 89 years ago the Great Flood of Louisiana implemented the existing levee system. Imperfect engineering and shoddy construction caused the collapse of dams, such as the Johnstown Flood of 1889. On May 16, 1874, 138 people died as a result of poor construction and a dam break in Williamsburg, MA. On March 12, 1928, the St. Francis Dam, in service less than two years, collapsed near Santa Paula, CA, killing 450. February 26, 1972, two coal slag dams along Buffalo Creek in southern West Virginia broke, unloading two miles of backed-up water into a lower dam that exploded, 4,000 homes were washed away with 125 deaths. June 5, 1976, the 305-foot Teton Dam in Idaho collapsed, released 80 billion gallons of water into adjoining farmland. It takes concrete to build levees and dams. Water is the most widely used material and second on the list is concrete and next to steel, concrete is the strongest material ever manufactured. Concrete cannot be fully recycled however a resurrected solution includes the use of lightning. Researchers from the Fraunhofer Institute for Building Physics in Holzkirchen, Germany revived a method, developed by Russian scientists in the 1940s, called electrodynamic fragmentation. The problem with recycling concrete is breaking down cement, water, and aggregate or the mixture of stone particles that consist of gravel and limestone grit. The process includes placing concrete in water then blasting it with a 150-nanosecond bolt of lightning. The bolt runs through solid material, creating a small explosion then tearing apart and breaking down its components. The fragmentation plant processes one ton of concrete waste per hour with larger volumes expected in the future.