Foundation (engineering)
Foundations are designed to have an adequate load capacity depending on the type of subsoil/rock supporting the foundation by a geotechnical engineer, and the footing itself may be designed structurally by a structural engineer. The primary design concerns are settlement and bearing capacity. When considering settlement, total settlement and differential settlement is normally considered. Differential settlement is when one part of a foundation settles more than another part. This can cause problems to the structure which the foundation is supporting. Expansive clay soils can also cause problems.
Stalactites (solitaire)
Before the game starts, the player can decide on how the foundations should be built. Building can be either in ones (A-2-3-4-5-6-7-8-9-10-J-Q-K) or in twos (A-3-5-7-9-J-K-2-4-6-8-10-Q). Once the player makes up his mind, he begins building on the foundations from the cards on the tableau. The foundations are built, as already mentioned, up regardless of suit, and it goes round the corner, building from King to Ace (if building by ones) or from Queen to Ace (if building by twos) if necessary. The foundation cards turned sideways, though not necessarily be done, is a reminder of the last card's rank on each foundation.