Masonry Magazine June 1992 Page. 14
In accordance with strict historic restoration guidelines for stone repair or replacement, Graciano removed the stones one at a time, photographed, numbered, and labeled them, taking care to protect the edges or corners from any damage during transport. Prior to installation, replacement stones were individually inspected by Mulcahy for texture and color match.
In the course of the Rhode Island State House restoration, Graciano found some marble blocks which were beyond repair and required replacement. For an exact match, we returned to Georgia Marble, the same quarry that had originally produced the blocks at the turn of the century. Gannet Backus, divisional manager, determined from which of the Company's three Georgia quarries the original stones had been cut. Sample blocks from the quarry were sent to Graciano to match the building's color and sandrubbed texture.
Color Photos Used for Match
White Georgia marble, a favored construction material, is extremely hard. Its density makes it less water permeable than sandstone or even granite, which gives it a very long life. The white variety of marble has fewer impurities than its green and black counterparts, thereby making it more monolithic and less subject to cracking. Aside from physical samples, color photographs were used to match the overall appearance and characteristic blue veining. Specifications required the marble to meet precise requirements of water ratio absorption by weight, density, compressive strength, modulus of rupture, abrasion resistance and flexural strength.
In addition to the white marble being replaced, several granite blocks also were replaced. As with the marble, granite samples were taken from the quarry and matched in color and texture to the adjacent stone on the building.
According to specifications, all replacement stone was required to be Grade A, free of any defects such as vents, cracks, fissures, sand or clay holes. Replacement marble was cut by Georgia Marble's Nelson plant and then transported to Providence for Graciano's final touches and installation.
The Providence State House dome is second in size only to the great dome of St. Peter's Basilica in Rome. The central rotunda of the State House rests on four huge columns, or tourelles. Through the years, the columns underwent extensive erosion due to the elements.
To retain the historic architectural integrity of the tourelles, Graciano's team developed a special system of epoxy injection to restore the structural soundness without defacing their exterior appearance. Cracks in the column scrolls and leaves on the east and west elevations were also repaired.
On the south face of the Governor's Balcony, balustrades and coping were crumbling, requiring section by section dismantling and reassembly. Over seventy balustrades were repaired or replaced along the balcony. Perhaps one of the most delicate and yet massive repair efforts on the project was the replacement of four intricately hand-carved 2,000 pound marble modillions which rest beneath the balcony windows. The old modillions were removed from their brackets and the openings were prepared for replacements. A nine inch diameter setting hole, three feet deep was cored into each new modillion (the "plugs" were saved for later use.) When the modillions arrived at site from Georgia, we inserted an eight inch diameter supporting pipe into the hole and fastened it by counter-sinking a U-bolt into a holding brace. We then replaced the plugs. The only modern technique Graciano employed throughout the project was the use of a crane to hoist the massive 2,000 pound blocks into position.
Cracks and spalls on the balcony's east and west stone faces also were in need of repair. When sectional repair was more economical than replacement, dutchmen were utilized. Cuts on the edges of replacement stones were made so as to be undetectable when they were in place. Stainless steel anchor rods were inserted diagonally to pin the stones into position. All moisture sensitive areas on the building envelope were sealed and caulked to prevent further infiltration and deterioration.
Approximately 120 window jamb stones had to be replaced or repaired due to damage caused by corrosion of security bars. In total, 350 such stones were dismantled and replaced. Window stones were small compared to others we reset, measuring only two feet by one inch.
Use Special Boatswain Rigging
To reach work areas high atop the building while the State House was in session and open to normal business traffic, Graciano utilized a special boatswain rigging in addition to conventional scaffolding techniques. The rigging allowed us to complete our restorations without interfering with the normal activities of the capitol as might have been the case if tubular scaffolding had been utilized.
In addition to the masonry, Graciano also cleaned and waterproofed the exterior ornamental structural metalwork. All metal such as the exterior brass railing around the lantern at the top of the dome and the podium of the south elevation stairs was cleaned and painted with rust preventative paints.
Before leaving Providence, Graciano's crew positioned several "modern" features on the dome lantern, colonnade, tourelles and other areas around the top of the building. These features also met project specifications-twenty lifesize fiberglass owls for bird control.
Urge Attendance at Board Meetings
EXECUTIVE BOARD MEETINGS for the Mason Contractors Association of America have been scheduled for this year, and plans are being finalized for 1993 meetings.
All MCAA members are encouraged to attend these special meetings, which are generally held in resort areas. The MCAA summer Executive Board meeting, for example, will be held at Harrah's in Lake Tahoe, Nevada, June 24-28. The fall Executive Board meeting will be held at Marriott's Castle Harbor Resort in Bermuda, October 31-November 1.
Although 1993 locations haven't been finalized, the American Club in Koehler. Wisconsin is being considered for the summer board meeting, and the Stouffer Maui in Hawaii is being considered for the fall meeting (which will be the kickoff location for the MCAA All Industry Tour of the Far East in 1993.)
Standing committees meet at the Executive Board meetings, and the Association's goals for the coming year are established. It's not all work there's ample time for relaxation. Even if you're not on a committee, members are urged to attend and give the Association the benefit of their input. Call the MCAA offices at 708/782-6767, for further information.