Multisensor and Automated Measurement of Bridge Deck Condition

摘要

This paper presents the results of a study that used multiple sensors to examine the condition of two reinforced concrete bridge decks.Some of the sensor systems were automated-others were manually operated.The Van Buren Bridge in Dumfries,VA was the subject of the most extensive examination.Two different ground penetrating radar(GPR)systems provided an automated noncontacting evaluation.One was the FHWA PERES system that uses micro-impulse radar and operates in the frequency range between 500 MHz and 5 GHz.A single antenna pair mounted on a linear drive mechanically sweeps across a 1.5 meter span,acquiring data every centimeter while the entire system is stepped forward in 1 cm increments.The second GPR system was the 3D-GPR.This is a step-frequency ground penetrating radar with 47 antennas that allows high-resolution measurements in a frequency range 100-2000 MHz.Impact echo(IE)measurements implemented in a Portable Seismic Property Analyzer(PSPA)provided complementary data.The PSPA is an ultrasonic/high frequency seismic device that incorporates ultrasonic surface wave(USW)measurement for elastic modulus evaluation and IE technique for delamination detection and characterization.Additional measurements included chain drag,half-cell and visual inspection.The second bridge was the Carter Creek Bridge in Irvington,VA.The testing involved use of the PERES GPR system,chain drag,half-cell and visual inspection.Preliminary observations during testing indicated that 3D-GPR was the quickest system followed by the PSPA,PERES and the fully manual methods.Data from these measurements will be analyzed for their respective capability of detecting damage,such as delaminations.The comparison will make use of overlay registration and visualization techniques.The potential for developing automated multisensor systems that fuse data for efficient and effective bridge deck measurements will also be discussed.