EDO6132 - Portland Castle; ground penetrating radar survey 2012

A Ground Penetrating Radar (GPR) survey was conducted at Portland Castle to assist with the investigation of ongoing water ingress through the external walls into an area known as The Captain's Chamber. The survey was carried out on the external walls from a two-tier scaffolding platform. Anomalies were recorded that related to the varying thickness of the outer wall and the location of known defects due to visible beam sockets on the inner wall. Further defects in the structural integrity of the wall were suggested including an area below the string corbell and areas where there were corroded ferrous fixings.