By Luke Carothers
The Robert Goud Shaw and Massachusetts 54th Regiment Memorial is located in America’s first public park: the Boston Common. The Memorial honors the first Black soldiers to fight for the North in the Civil War. Despite public opposition, members of the 54th Regiment performed heroic deeds at the Battle of Fort Wagner in South Carolina, inspiring over 200,000 Black soldiers to enlist in the Union cause.
Among the heroes of the 54th Regiment were soldiers like Sergeant William H. Carney, who, despite being severely wounded, was able to save the Regiment’s flag at the Battle of Fort Wagner. This act earned Sergeant Carney the Medal of Honor, for which he was the first Black soldier to receive the honor. In their heroic efforts, Shaw and many of his men were killed in the assault of Fort Wagner.
In an effort to honor the sacrifice of Shaw and his men, private donors raised funds for the creation of a memorial to be placed in the Common. Notable artist Augustus Saint-Gaudens spent nearly 14 years modeling the faces of more than 40 men to create a high-relief bronze monument, which was unveiled to the public in 1897.
In 2013, observations were made that several of the large stones at the front of the monument had shifted significantly. This led to probing of the monument, which revealed that the brick core supporting the bronze relief had been deteriorated due to water infiltration and annual frost/thaw cycles. These investigations also revealed that there was significant corrosion on the steel beams that supported the plaza from below.
In order to compensate for these issues, temporary work was done to stabilize the monument. This included actions like adding temporary supports below the plazas and limiting the flow of water by replacing defective sealants and mortar and covering some of the upward facing joints with lead flashing. While these short-term additions served to stabilize the Memorial, it was clear that it needed a complete restoration.
In order to complete the necessary restoration, a partnership was formed between the Friends of the Public Garden, the City of Boston, the National Parks Service, and the Museum of African American History. Through the bidding process, this partnership tapped several firms to lead the project. Silman served as the prime consultant and structural engineers for the project, headed by Ben Rosenberg. Sculpture and Decorative Arts Conservation Services (SDACS), led by Barbara Mangum, served as the bronze conservator. In addition, Building and Monument Conservation, led by Ivan Myjer, served as the stone conservator for the project.
Echem served as a design consultant for the project as cathodic protection specialists. Additionally, AHA joined the group as electrical subconsultants, supporting the cathodic protection and lighting for the project. On the contracting side, Allegrone was tapped as the construction manager.
The teams tapped by the partnership had a tall task at hand. With more than 100 years of exposure to the elements and only period maintenance and repairs, the team set about assessing the greatest areas of need for the structure. The team referred to this as the “investigation phase”, and it included measures such as visual observations, material testing, and probes to remove some of the stones and determine the state of the substructure. Once these tests and observations were completed, it was clear there were a number of significant issues facing the structure. For the team, the question then became what not to do. Both kinds of stone, granite and marble, were experiencing significant deterioration as well as the bronze. There was also a need to address both the vertical support–which holds up the monument–and the horizontal support–which holds up the visiting area of the monument. To add to this, there was also the desire to prevent further deterioration on the site. The restoration project was determined by five scopes: stone, bronze, structural work, cathodic protection, and ancillary work.
To begin restoring the monument, the team first focused on the bronze relief. Maintained by the Friends of the Public Garden since the 1980s, the bronze relief was one of the areas of the monument that had succumbed the least to deterioration. Because of the positive state of the relief, there was no need to remove it directly for restoration. However, due to the compromised nature of the substructure, the relief had to be removed to make room for the restoration teams. On top of allowing the team to complete a comprehensive restoration, this off-site removal afforded unique views of the monument that had never been seen before, such as the back, which revealed key insights into the making of the monument. In addition, there was a discolored area in the top left section of the relief that posed somewhat of a mystery to the restoration team. Further analysis showed that the discolored area included a high amount of iron, likely a contamination during the casting process that rose over the years. This analysis gave the team the confidence to correctly fix the area.
Much in the same way as the process behind the bronze relief, the team had to make a decision as to where the stone portions of the monument would be restored. Additionally, the team had to decide how much of the stone would be removed for restoration. Ultimately, the team opted to remove roughly 85 percent of the stone in the monument for intensive cleaning and restoration that included things like infill and removal of deteriorated stone, leaving a small portion of stone around the back.
With the bronze and stone removed, the true breadth of the restoration project was revealed. Although the team had taken probes of the monument and determined that the core structure of bricks had been compromised, there were still quite a few unknowns. Although there were extensive surveys of the monument taken and the original drawings were analyzed, the team was still unsure about some of the dimensions of the internal structure such as the distance between the stone and bronze, and how those two elements were connected. Once the bronze was removed, it was clear there was no anchoring between the two elements. With this question answered, the team was able to fit the dimensions of a stainless steel frame to support the vertical section of the monument. In addition, the team installed a stainless steel plate and sleeve to support the bronze legs at the bottom of the statue and prevent lateral movement.
Next, the team turned to reinforcing the plaza upon which the monument is viewed. Beneath the plaza there is a series of steel beams spanned by brick arches. When the team first entered the crawl space beneath the plaza, it was immediately clear that there was significant damage to the structure including rust and other signs of deterioration. After this initial survey, the team had to decide whether to rip up the plaza and completely replace the structure or repair the original structure. The team opted to repair the original structure, employing the use of cathodic protection to prevent further deterioration to the steel support beams that were embedded in the brick arches. While cathodic protection does not reduce the damage already done to the structure, the system minimizes or prevents further damage from being done. The team also scraped, cleaned, and applied corrosive-resistant paint to the exposed portions of the steel.
With the entire restoration process completed in a little over a year and a half, the monument is scheduled to be rededicated on October 20th, 2021. Through the efforts of the partnership, future generations will be able to explore, learn, and benefit from this historical monument for generations to come. “The actual foundation of the Memorial both inspired and is at the heart of the restoration efforts. With our Partners the National Park Service, the City of Boston, and the Museum of African American History, we are using our restoration of the Memorial as a platform to explore issues of race, social justice, and inclusive placemaking,” said Liz Vizza, president of Friends of the Public Garden on behalf of the Partnership team. “Fortifying the foundation and telling the fuller stories of the public art that inhabits our shared spaces like America’s first public park are catalysts that brings people together, creates community, and furthers a richer and deeper understanding of our shared history and future for many generations to come.”
Luke Carothers is the Editor for Civil + Structural Engineer Media. If you want us to cover your project or want to feature your own article, he can be reached at firstname.lastname@example.org.