Structure mapping through spatial and temporal deformation monitoring using persistent scatterer interferometry and geographic information systems

Many engineering professions have adopted asset management procedures to properly construct, monitor, maintain, and support physical assets through the full service life-cycle of all assets within a network. All asset management programs, whether structural, geotechnical, or transportation, have one common goal: to achieve life-cycle performance goals (e.g., safety, preservation, economic and environmental sustainability, etc.) by cost-effectively managing physical structures. Monitoring deformation rates across an asset can be used as an indirect method of obtaining initial condition assessment information, which is vital for understanding an asset’s current life-cycle stage. Persistent scatterer interferometry (PSI), an interferometric synthetic aperture radar remote sensing stacking technique, is capable of measuring displacement rates at 1 mm/year accuracy on anthropogenic infrastructure not undergoing immediate, catastrophic failure. Geographic information systems (GIS) allows storing, processing, analyzing, and displaying geographic data. By combining PSI and GIS capabilities, this paper will illustrate how these techniques can be utilized to spatially and temporally map deformation rates on a variety of assets, and how an initial condition assessment can be made on each asset. Structure mapping can be conducted in four steps: (1) digitization of geographic location for all structures; (2) processing of radar imagery, which results in displacement rate data for all viewable structures; (3) spatially analyzing displacement rates and assigning PS points to individual structures; (4) producing maps, including both spatial and temporal information (e.g., displacement-time series analyses). This procedure will be demonstrated using 40 COSMO-SkyMed satellite radar data, 3 m resolution images acquired between July 2012 and September 2014, over urban infrastructure in San Pedro, California