- The United States Department of Labor (DOL) is one of the executive departments of the U.S. federal government. It is responsible for the administration of federal laws governing occupational safety and health, wage and hour standards, unemployment benefits, reemployment services, and occasionally, economic statistics. It is headed by the secretary of labor, who reports directly to the president of the United States and is a member of the president’s Cabinet.
- Why Bridges Don’t Sink (practical.engineering)
The essence of a bridge is not just that it goes over something, but that there’s clear space underneath for a river, railway, or road. Maybe this is already obvious to you, but bridges present a unique structural challenge. In a regular road, the forces are transferred directly into the ground. On a bridge, all those forces on the span get concentrated into the piers or abutments on either side. Because of that, bridge substructures are among the strongest engineered systems on the planet. And yet, bridge foundations are built in some of the least ideal places for heavy loading. Rivers and oceans have soft, mucky soils that can’t hold much weight. Plus, obviously, a lot of them are underwater.