Correlation between GPR data and historical documentation for assessing the pavement constructive phases of Los Silos of Burjassot, 16th century (Valencia, Spain)

This paper describes GPR survey performed in the square of Los Silos of Burjassot (1573-1806) in order to detect the location of the total number of silos and the different constructive phases in correspondence with historical documents. This is the first analysis performed in this architectural heritage built in the 16th century. Los Silos of Burjassot was erected to house the underground grain storage of Valencia. This construction is composed of three buildings and a big square beside them, under which 41 silos are placed. During the construction, between 16th and 18th centuries, many pits were filled in because of different reasons and the square was completely paved, following diverse structural systems. Thus, in order to reveal the location and the exact number of silos, as well as to corroborate the constructive phases of the pavement with historical documentation, the GPR survey was directed on the 73x70 m square. A Ix1 m grid, composed of 141 orthogonal profiles, was collected using a GSSI SIR3000 equipment and a 400 MHz frequency antenna, for reaching 1.5 m depth. After the GPR data analysis, 6 non-documented anomalies were detected; and a variable compacted soil stratum and a mortar layer under the pavement were identified. Besides, the 7 constructive phases of the pavement were delimitated in correlation with historical documentation. These results demonstrate GPR is a non-destructive technique suitable for efficient and respectful studies for architectural heritage.