Hoover Dam in Nevada

Located in Nevada, Hoover Dam is a place that’s worth a day visit to go see. Built to create Lake Meade, and control the Colorado River, Hoover Dam is one of the most recognized man made constructions around. One of the most interesting facts about the Hoover Dam is that it contains more masonry than the Pyramid of Giza.  Three and one-quarter million cubic yards. There are 4,360,000 cubic yards of concrete in the dam, power-plant and appurtenant works. This much concrete would build a monument 100 feet square and 2-1/2 miles high; would rise higher than the 1,250-foot-tall Empire State Building if placed on an ordinary city block; or would pave a standard highway 16 feet wide, from San Francisco to New York City.

The first concrete for the dam was placed on June 6, 1933, and the last on May 29, 1935. Approximately 160,000 cubic yards of concrete were placed in the dam per month. Peak placements were 10,462 cubic yards in one day (including some concrete placed in the intake towers and powerplant), and slightly over 275,000 cubic yards in one month.

The dam was built in vertical columns of blocks that varied in size from about 60 feet square at the upstream face of the dam to about 25 feet square at the downstream face. An estimated 215 blocks make up the dam. Adjacent columns were locked together by a system of vertical keys on the radial joints and horizontal keys on the circumferential joints (think “giant Lego set”). Concrete placement in any one block was limited to five feet in 72 hours. After the concrete was cooled, a cement and water mixture called grout was forced into the spaces created between the columns by the contraction of the cooled concrete to form a monolithic (one-piece) structure.