TY - JOUR A1 - Lai Wai-Lok, Wallace A1 - Kind, Thomas A1 - Wiggenhauser, Herbert T1 - Frequency-dependent dispersion of high-frequency ground penetrating radar wave in concrete JF - NDT & E international N2 - This paper studies the dielectric dispersion of high frequency radar wave in concrete in early-aged and hardened concrete specimens. Frequency-dependent spectra of phase velocity ν(ω) were measured to deduce the spectra of real part of dielectric permittivity ε'(ω). The dispersion was measured by three high nominal ground penetrating radar frequencies (1.5, 1.6 and 2.6 GHz), experimenting on two steel bars with concrete cover 50 and 100 mm. It was found that ν(ω) and ε'(ω) dispersed at lower frequency, but became stable at high frequency regions, which agrees with the classical GPR plateau. The same frequency components at different nominal antenna frequencies show a close range of ν(ω) and ε'(ω) in concrete of different ages. The results in this paper warrant further investigation of using GPR wave to study material properties. KW - Frequency-dependent dielectric dispersion KW - Ground penetrating radar (GPR) KW - Phase velocity KW - Real part of dielectric permittivity KW - Concrete PY - 2011 DO - https://doi.org/10.1016/j.ndteint.2010.12.004 SN - 0963-8695 VL - 44 IS - 3 SP - 267 EP - 273 PB - Butterworth-Heinemann CY - Oxford AN - OPUS4-26289 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -