Historical retaining walls monitoring: a case study of debosquette wall of kyiv-pechersk lavra

Geospatial monitoring of historic buildings has a valuable meaning for their restoration and preservation measures. The preparation and accomplishment of such monitoring have their features and cannot be standardized. Therefore, in each particular case, monitoring is carried out for specific requirements and conditions. The paper presents the results of geospatial monitoring for a part of the UNESCO object Kyiv-Pechersk Lavra. The primary subject of geospatial monitoring is a retaining wall known as the Debosquette Wall. The wall was built in the XVIII century and underwent restoration in 2014. A geospatial monitoring system has been established to prevent undesirable damage and displacements. Assigning the necessary observation accuracy for such a complex object is difficult. In the paper, the modern approach to observation accuracy calculation has been suggested and studied. The approach is based on the application of structural mechanics principles. The structural analysis of the Debosquette Wall has been accomplished. The output of the analysis was applied to calculate the required observation accuracy. The geospatial network and monitoring scheme were developed based on the calculated accuracy. The monitoring proceeded for half a year in 2012-2013, was interrupted for one year, and kept on in 2015. The primary stress was made on the horizontal displacements in that these displacements are the primary threats to the wall stability. The in-depth analysis of the monitoring results has been accomplished. It was found that the displacements have stayed within the allowable values. The developed monitoring approach is recommended for similar projects.