To Do: Migrate

This poster is part of Preserving U.S. Military Heritage: WWII to the Cold War, Fredericksburg, Texas, June 4-6, 2019.

by Patrick Sparks


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This poster-presentation describes the structural condition assessment, recommended conservation approaches, and field demonstrations for the on-going efforts to preserve the WWII Japanese buildings on Peleliu Island, Republic of Palau.

The battle for Peleliu Island was one of the most brutal battles in the Pacific war.  Its battlefield is largely intact, with most of the original Japanese buildings and defensive structures still standing.  In particular, battle damage to the reinforced concrete buildings is essentially unchanged since the war.

The extant buildings have damage both from the battle and from corrosion of the reinforcement.   Of the battle-damage, the most serious structural issues where entire walls or columns were lost.  Even in those cases, however, there are few unstable elements today.  The battle damage, including the blast holes and the associated deformed steel reinforcement, are a character defining feature of the buildings indicative of the intensity of the offensive action.   Where it has been exposed by battle damage, the reinforcement is to be left exposed to aid in the battle interpretation.  On the other hand, where the reinforcement has become exposed due to environmental effects, it should be preserved by appropriate methods of concrete repair.

In addition to the structural condition assessment, a limited field effort, primarily focused on the Museum Building, achieved some preliminary goals in the conservation and helped define some possibilities and challenges.  The poster will present the application of a protective coating on the roof, a concrete re-alkalization demonstration at blast damage area, vegetation treatment and removal, and other structural recommendations.


Patrick Sparks is president of Sparks Engineering, Inc., a consulting firm specializing in the investigation and rehabilitation of historic structures.  He is a Professional Fellow of the Center for Heritage Conservation at Texas A&M and is an expert member of International Scientific Committee for the Analysis and Restoration of Structures of Architectural Heritage.  Among other projects, he was responsible for structural stabilization of 18th century churches in the San Antonio Missions World Heritage Site, the rehabilitation of the historic Rio de Manatí bridge in Puerto Rico, and conservation of WWII concrete structures on Peleliu Island, Republic of Palau, and the 2016 DoD study: Implementing Environmental & Economic Cost Benefits of Reusing DoD’s Pre-World War II Buildings.

National Center for Preservation Technology and Training
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