Masonry Magazine June 1992 Page. 13
nearly forty tons of replacement Georgia marble and 51,069 man hours to complete.
The immense undertaking of the $4-million project began with chief engineer, Joe Mulcahy of Mulcahy Engineers, in Cranston, Rhode Island. Mulcahy's firm surveyed the entire structure and painstakingly outlined the exact repairs and restoration systems to be used in accordance with Rhode Island Historical Preservation Commission guidelines.
Graciano's chief engineer inspected the project and developed the written plan to complete the restoration within budget guidelines. We then assembled a restoration team of some thirty-five local Providence and Pittsburgh artisans managed by Jim Johnston, project manager. This team was skilled in masonry restoration, stone carving and fabrication, masonry installation, metalwork, waterproofing and tuck pointing.
The first step of the complicated two-year project was a low pressure water cleaning of the exterior facade working down from the top of of the building. Because of the historic significance of the building, the most vigorous cleaning was limited to hand-scrubbing with soap, water and stiff brushes so as not to harm the stone's patina in any way.
Three Challenging Areas
After completing the initial surface cleaning, the actual restorative repairs began. Three particular areas posed the greatest challenge for the restoration team: the massive entry steps, replacement of several large ornamental modillions, and the dome.
In addition, the project called for the restoration of the main terrace, east retaining wall of the north plaza, and replacement of the south steps. Prior to the start of stone cutting and repointing of the building joints, our crew first had to complete masonry repairs.
Each day mortar samples were taken from specific joints and analyzed for content and composition ratios in order to reliably ensure color and strength. According to project specifications, replacement mortar had to both visually and physically match the original. No chemical bonding or entraining ng elements were used. After cleaning away all loose soil by hand, air jets removed particles of old material from the joints to allow for repointing.
Prior to mortaring, the joints were prepared with water to allow better adhesion of the new mortar. After the mortar was dry to the touch, craftsmen hand tooled it to match the de-
THE PROVIDENCE, Rhode Island State House dome is second in size only to the great dome of St. Peter's Basilica in Rome. The State House itself is 333 feet by 180 feet wide and 235 feet high, with over 15-million stone, masonry and brick units. Restoration project required 51,069 man hours to complete.
tailing of the original builders. Lead cames were then removed from the old joints at the parapet coping, at the eaves, and the water tables.
The joints were cleaned and filled, new backer rods and replacement cames were installed. After the mortar was applied, our crew saw cut and hand chiseled mortar joints around the exterior surface of the building.
Extensive Rebuilding of Steps
Since the last restoration of the State House in 1962, subsurface ground shifting and weather erosion had caused the south steps to deteriorate. The steps were uneven and some serious water damage had occurred to the foundation. Graciano repair involved extensive underside support, demolition and rebuilding.
Subflooring and archways were completely restored. The underside brick capping (or subbase) was re-grouted and sealed to prevent further water damage. After completing repairs to the foundation, we turned to the restoration of the colossal marble steps. Each step was comprised of twenty six-foot marble segments weighing nearly one ton each. All of the marble segments were either replaced or reset.
The 160 foot x 30 foot east retaining wall on the north patio buckled over time, was dismantled stone by stone. Stones in the wall were approximately 2 feet x 4 feet and from four to eight inches thick. Their individual weight ranged between 600 to 800
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