Radar measurement of density variations around an arch bridge

摘要

This paper describes a novel application of Ground Probing Radar (GPR) to the assessment of backfilled brickwork arches. The method provided a rapid and cost-effective means of determining the spatial variation of density in the backfill around a brickwork arch. Independent calibration of radar density measurements was undertaken by sand pluviation and subsequent manual density measurement. Density variations of the order of 2 kNm~(-3) were detected by the correlation of radar and pluviated density measurements. Significant density gradients were detected by the successful correlation of porosity, and hence density with dielectric constant.