Existing Foundation Exposures

Existing Foundation Exposures can be undertaken to aid subsidence claims or to detail the existing footings with regards new footings or where additional load may be applied to existing structures.

Subsidence

Where existing buildings are undergoing movement and cracking has appeared within the structural fabric of a building, HESI can attend and review the existing foundation depth, condition and profile and undertake hand auguring through the base of the excavation for the recovery of samples for visual and laboratory review to assess any risk which may be in place. This may include identification of root samples which can be identified to a source tree such that specific identification of the cause of movement can be recorded and will aid in the remedial measures which could be implemented to stabilise the structure. 

The details of the foundations and the subsoil are noted and recorded for later use within a report. Also, undisturbed, or disturbed samples can be recovered by these techniques.

In-situ bearing capacities are also noted at 0.50m intervals throughout the borehole, with all excavations internal or external being replaced to the condition found.

These works are generally undertaken by a two-man crew and completed within a single working day, although, multiple days can be organised. 

Additional Loading

Similar to above, the profile of the foundations around a structure can be recorded and assessments of the soils directly beneath the foundations made to review allowable bearing capacity for potential additional loading. A review of the soil profile over depth is also undertaken to confirm the geology and any possible surcharge loads which may take place and ensure suitability for the additional load. 

Foundation exposures are vital in understanding what the source of existing structure movement may be.