A tough and heavy rock-like material made from pulverized stone. Concrete is used in building several items in settlements, most notably foundations for houses and water pumps, as well as statues and other decorations. The Wasteland Workshop add-on introduces a large number of additional items which require a fair amount of concrete to construct.
Concrete can be found throughout the wasteland in the form of a bag of cement. Another method of obtaining concrete is through scrapping broken down houses, or from cinder blocks. There are several cinder blocks littered in front of and to the right of the shack at Tenpines Bluff. Home Plate has a considerably large amount of cinder blocks lining the bottom floor of the house, and Graygarden has several cinder blocks scattered across the build area, also at The Castle in the underground tunnels there is a room with multiple shelves with a ton of bags of cement.
Often there will be "seats" around a cooking station. Moving the station will allow the Sole Survivor to find those extra cinder blocks and concrete.