报告人： Ming Wang博士，美国东北大学土木与环境工程系 杰出教授
地点： www.95990055.com,九五至尊老品牌朝晖校区北门 特种装备制造与先进加工技术重点实验室 A206
Air-coupled Ground Penetrating Radar System Operated at Traffic Speed for
Pavement and Bridge Applications
COE Distinguished Professor, Northeastern University, Boston, MA, USA
The GPR system is operated at center frequency of 2 GHz with a penetration depth of 60 cm in common road materials. The features include capability of collecting up to 1000 traces per second, large dynamic range, and compacted profile. Using a four channel GPR array, a large amount of data is collected at traffic speed on urban roads for over 200 lane miles providing a dense spatial coverage. First, the surveyed GPR data contains information about the pavement layer properties, including layer interface, dielectric constant, and layer thickness. Using cross correlation and Hilbert transform algorithms; the pavement layer properties are identified from the large GPR data sets in an automatic and efficient way. Second, we will talk about the results using automatic algorithm to detect steel rebar in concrete bridge decks. The surveyed GPR data from reinforced concrete (RC) structures carries significant amount of information, such as rebar location, dielectric constant of concrete, corrosion condition of steel rebar, and so on. However, current methodologies to detect rebar from GPR data are either manual or iterative, which is time-consuming. An unsupervised, efficient, and robust algorithm is validated by the GPR data collected from several decommissioned RC slabs, which were cut from a highway bridge. The reflection amplitude extracted from the top of rebar is used for creating a corrosion indicator map, which has shown very good agreement with the results of half-cell potential.
Ming Wang is a Distinguished Professor of Civil and Environmental Engineering at Northeastern University. He is the PI and Director for VOTERS Sensor Systems since March 2009. VOTERS (Versatile Onboard Traffic-Embedded Roaming Sensors) aims to provide a continuous stream of accurate, up-to-date information about the state of roadways and bridge decks gathered by sensor systems mounted on vehicles of opportunity, while also eliminating the hazardous, congestion-prone work zones that are often set up to gather this critical data. The VOTERS project is funded under the Technology Innovation Program (TIP) of NIST and will run for five years at a total cost of $18 million, including cost-sharing by the project participants. The VOTERS team includes more than 40 members including faculty, research scientists, administrative staff, and graduate students from three universities as well as research engineers and consultants from several industrial partners. Professor Wang is a fellow of SPIE.