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The goal of the overall conditions survey was to rank each of the 567 tiles on a scale of 1 to 10, with 1 representing the worst condition and 10 representing the best. By giving a value to each tile, and a color to each value, tiles in good, fair, and poor conditions can be easily identified as well as areas with high or low concentrations of each. The initial survey was done by hand and then transferred into Arc View (ArcGIS) for quantification.


Two site visits were made in October and November, 2006 and were dedicated to clearing the pavement of vegetation and sweeping each tile to collect and bag loose material. Each tile was given an alphanumerical tag for identification and each bag containing material from a tile was labeled correspondingly. The condition rating assigned to each tile was based on an overall assessment of the tile condition rather than an average of separately rated factors. The overall assessment of the condition of each tile considered the degree of cracking, deformation, and integrity (i.e., presence or lack of original material). A high value reflects a higher integrity and quantity of original fabric and a low percentage or area of loss.


Integrity was rated on a scale of 0-10. No tiles were given a value of 10. A value of 0 indicates a tile that has been completely replaced by cement. The majority of tiles, 24% of the 567 tiles, received a value of 6. The percentages for the remaining tiles are in descending order as follows: 7=22%, 5=13%, 4 and 8 =10%, 3=6%, 2=5%, 1, 9=4%, and 0=3%. Map 1 in Appendix C, shows the percentages of each condition number in pie chart format.


Three broad categories (good, fair, and poor) were created to better understand and visualize the extent of the deterioration of the pavement. The survey reflects the level of integrity of the tiles and the approximate percentage of loss that they display. Tiles given a value of 6-9 display a range of approximately 0-10% loss (good condition); tiles with a value of 3-5 display approximately 10-30% loss (fair condition), and tiles with a value of 0-2 display approximately 30-100 % loss (poor condition), including those that have been replaced by concrete. Tiles with values ranging from 6-9 make up 59% of the tiles of New York State; values ranging from 3-5 make up 29% of the State; and tiles with a value of 2 or less, including those with no data recorded make up 12% of the State. This suggests that more than half the pavement is in reasonable condition with less than 10% loss.

 

It is important to make a correlation between the deterioration of the representative tiles from Long Island and the entire map. The overall assessment provides a broad overview of the areas that are in good, fair, and poor condition. The similarity between the overall values assigned to Long Island and the corresponding percentages of the tiles with the highest level conditions rating provide a framework for determining the level of damage present and ultimately the kind of intervention that may be needed on the rest of the pavement.
The tiles that were given a lower value in the overall survey, and tiles that display the highest percentages of the represented conditions, are located in the western portion of Long Island close to New York City. A comparison between the overall values assigned to each tile and the percentage range of a particular condition per tile in Long Island, shows the correlation between the overall number and the degree of damage. Map 3 (Appendix C) shows the comparison between the percentage of tiles displaying loss, fill, and the overall condition.


The four tiles that were conserved as part of the exhibit at the Queens Museum of Art in spring 2008 were all given a value of 6 on the overall survey of the pavement. While there were differences in their configurations and the way they conserved, it gave us a good sense of how the values can be used to determine the level of intervention necessary, and ultimately, what percentage of the pavement can be retained rather than replaced. Tiles given a value of 6 represent 24% of the pavement, while tiles with a value of 6 and higher represent 59% of the pavement. More than half of the tiles of the pavement have a condition value that is the same or better than the four tiles that were conserved.


The initial survey estimated that tiles with a value of 6 displayed 0-10% loss. While this may be the case when the tiles are in situ, there is a certain amount of damage and loss that occurs when the tiles are removed for conservation. Additionally, the value assigned considers the plastic insets as well as the terrazzo. Tiles with a high level of intact insets were considered to be in better condition, even if they were missing a significant amount of terrazzo due to the difficulty of replicating the exact design layout. The initial estimate of 0-10% loss is more accurate regarding the loss of insets than the loss of terrazzo.