Gravity Dam: Forces Water pushes against the gravity dam, but the heavy weight of the dam pushes down into the ground and prevents the structure from falling over.
There's even more to explore at the BUILDING BIG web site, check it out at www.pbs.org/buildingbig.
BUILDING BIG is a coproduction of the WGBH Science Unit and Production Group, Inc., and is presented on PBS by WGBH Boston.
Major funding is provided by the National Science Foundation. Additional funding comes from the National Endowment for the Humanities, The Arthur Vining Davis Foundations, the Corporation for Public Broadcastin, and public television viewers.
National corporate sponsorship is provided by the American Society of Civil Engineers and by Siemens.
There's even more to explore at the BUILDING BIG web site, check it out at