Tall and heavy buildings are most often founded on slab or box foundations.
Foundations of tall buildings: a) slab foundation, b) box foundation; 1 – Lean concrete, 2 – foundation plate, 3 – stem, 4 - pole, 5 - wall, 6 - ceiling, 7 – armaments.
Figure a shows a slab foundation under a building with a shaft-shell structure, or molar–framework, while in fig. b shows a box foundation. In addition, these foundations can be used under buildings erected on soils showing uneven settlement, and in mining and seismic areas..
The box foundations form the slabs: foundationowa (lower) and ceiling connected with internal and external perimeter walls. These foundations are used for frame buildings, longwall-frame and molar-skeleton. In case of, when soils of the required bearing capacity lie deeper under the surface, then it is advisable to use deep foundations, to which they belong: poles, pale, wells and caissons.