Forensic Investigations of the Soil-Structure Kind

The authors were retained to perform independent forensic investigations as a check on the work of other investigators at two distant, independent apartment complexes. Buildings at the complexes had experienced distress. In one case, distress was attributed to ground movement due to settlement of fill in a previously undetected buried creek channel, a conclusion based on the observation of asphalt concrete revealed in a deep test pit. An expensive repair scheme involving pressure grouting was proposed. In the other case, the various forms of structural distress, which included cracking of floor slabs, was attributed to excessive wind loads. Demolition and reconstruction of the distressed structures was recommended. The authors' investigations incorporated valuable information from fields of expertise other than engineering. Identification of the actual causes of damage to the apartments in both cases was critical for the development of appropriate and cost-effective repairs and remediation. One lesson learned was that there should be no reluctance to pursue apparently distracting leads when investigating the true cause of failures.