Friday, June 17, 2011
To achieve the goals of stabilizing the markers, the brownstone, marble and slate is being cleaned of biological growths and accumulated dirt and soiling. Delaminating (or flaking) areas are being re-adhered using epoxies and acrylic adhesives injected between the bedding planes, small cracks and fissures. Open seams and voids are being packed and filled with natural and polymer modified mortars specifically designed for use on historic objects. These techniques are used to keep water from infiltrating and pooling in the damaged areas, which in turn limits the possibility of the freeze-thaw cycling that damages historic stone structures and objects.
In some cases, broken sections are being re-attached with stainless steel pins and epoxy. Some of the marble elements are being consolidated with a stone consolidant that allows for the passing of water vapors from the substrate to the surface. These techniques are used to strengthen the most degraded stones.
Posted by Historic Boston Inc. at 12:36 PM