Beam Strip Raft.

The beam strip raft consists of (ground-bearing) downstand beams in two or more directions which support the heavy uniform or point loads from the structure. The beams are tied together by a ground-bearing slab supported on the hardcored dumplings, i.e. the raised areas of hardcore protruding up between the beam lines (see Fig. 9.28).

This raft is mainly used in areas of either mining activity or soft alluvial deposits where a stiffened beam is required  on the main load lines. The tying of the ground floor slab into the beams prevents lateral distortions of the beam and evens out any local differential settlements. This type of raft is more economic than the cellular form and is used where conditions are not as severe.

Fig. 9.28 Beam strip raft.