Post-Construction Foundation Failure.

A foundation that has been designed well and has performed perfectly satisfactorily, may suffer distress due to nearby disturbance. Typical examples of such disturbance are piling for a new adjacent building; rerouting of heavy traffic; new heavy hammering plant installed in adjoining factories; and other activities which may vibrate or send impact shocks through the soil under the existing foundation, thus causing compaction and further settlement, which may be unacceptable.

Similarly, changes in the moisture content (by increasing it due to leaking mains and drains or by the removal of trees, or decreasing it by introducing drainage paths due to neighbouring excavation or by further growth of trees)  can disturb the state of equilibrium of the soil/foundation interaction. An interesting case, investigated by the authors’ practice, was the deforestation of land uphill of a factory.

The increased rain water run-off seriously affected the basement of the factory.

The construction and loading of new foundations may disturb existing buildings. The rising level of the water-table in cities due to the cessation of artesian well pumping is also causing problems (see Chapter 4 on topography, and CIRIA Special Publication 69, The engineering implications of rising groundwater levels in the deep aquifer beneath London).