Not only a concrete term.
Struts and whalers are the beams used to support sheet piling. Often sheet piling in driven into the ground so the interior soil can be removed. The whalers are fastened to the face of the sheet piles ( much like has been described for concrete forms), and the struts run across the excavation, bracing one wall against the other, and bearing on the whalers.

__________________
1982 300SD " Wotan" ..On the road as of Jan 8, 2007 with Historic Tags