GeoMeasurements by Pulsing TDR Cables and Probes

Book excerpt: GeoMeasurements by Pulsing TDR Cables and Probes examines Time Domain Reflectometry (TDR) research and provides information on its use as a robust, reliable, and economical production tool. Common uses for TDR technology include telecommunications and power industries, but the text examines applications such as measurement of moisture of unsaturated soils; detection of fluids for leak and pollution; measurement of water levels for hydrological purposes; measurement of water pressures beneath dams; and deformation and stability monitoring of mines, slopes, and structures. Chapters discuss: basic physics of signal generation, transmission, and attenuation along the coaxial cable probe designs and procedures for calibration as well as the variation in probe responses to changes in water content and soil mineralogy variations in waveform characteristics associated with cable, deformation, cable calibration, and installation techniques for metallic cables in rock several cases demonstrating the use of TDR cables in soil as well as weathered and soft rock a rationale for the use of compliant cable in soil the use of metallic cable (MTDR) and optical fiber (OTDR) to monitor response of structures sensor/transducer components, connections from the sensors to the TDR pulser/sampler, and system control methods available software for transmission and analysis of TDR signatures The diverse interest and terminology within the TDR community tends to obscure commonalities and the universal physical principles underlying the technology. The authors seek to crystallize the basic principles among the seemingly divergent specialties using TDR technology in geomaterials. By examining varied experiences, GeoMeasurements by Pulsing TDR Cables and Probes provides a synergistic text necessary to unify the field.