Forensic investigation of a damaged concrete building: causes and remedial measures

This paper presents a forensic investigation methodology which was adopted to identify the causes of deterioration and damage due to groundwater leakage beneath a reinforced concrete (RC) building. Extensive visual inspection, structural, geotechnical and geophysical investigations were used to identify the causes of the problem, assess the structural stability and integrity of the affected building. This study found that the main cause of underground water intrusion into the basement room is from irrigation of lawn and trees that surround the building where the water level was depicted at a depth of 3 m. The geotechnical and geophysical investigations were consistent and revealed the presence of a variable fill layer followed by a thin top layer of medium dense to dense sand followed by weathered conglomerate overlying sandstone. Shutting off the irrigation systems and the removal of the lawns and trees from the immediate vicinity of the building resulted in the stoppage of water intrusion into the basement within 90 days. The study concluded that the building is stable, while precaution remedial measures are recommended to prevent further deterioration. This study also highlights the effectiveness of combining geophysical and geotechnical methods for forensic analysis of damaged buildings.