TY - CONF A1 - White, J. A1 - Wolf, Julia A1 - Shokouhi, Parisa A1 - Hurlebaus, S. A1 - Wimsatt, Andrew T1 - Concrete tunnel lining evaluation using nondestructive techniques: a multi-method case study at Eisenhower tunnel T2 - TRB 92nd Annual meeting N2 - An in-depth investigation of tunnel linings is performed at Eisenhower Tunnel, 60 miles west of Denver, Colorado, using a combination of four nondestructive testing methods: air- and ground-coupled ground penetrating radar (GPR), ultrasonic echo (US echo), ultrasonic tomography (UST), and impact echo (IE). A robotic frame with pneumatically operated vacuum plates is used to automate GPR, US echo, and IE. UST was performed manually. These techniques are used to identify and locate the reinforcement mesh and structural steel ribs. Local changes in ultrasonic phase are calculated by phase analysis processing techniques and apparent relationships between positive and negative phase shifts and steel and air interfaces are observed. According to previous laboratory research, these relationships indicate the bonded state between the concrete and the embedded steel, but without ground truth verification this can only be suggested. It is shown that this combination of methods can be used synergistically to provide tunnel owners with the layout and possible condition of tunnel lining reinforcement and structural components. T2 - TRB 92nd Annual meeting CY - Washington, D.C., USA DA - 13.01.2013 KW - Nondestructive evaluation KW - Concrete KW - Ultrasonic KW - GPR KW - Impact echo PY - 2013 UR - http://trid.trb.org/view.aspx?id=1242002 SP - 1 EP - 16 AN - OPUS4-32025 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - White, J. A1 - Wolf, Julia A1 - Shokouhi, Parisa A1 - Hurlebaus, S. A1 - Wimsatt, Andrew T1 - Nondestructive evaluation of concrete linings at Hanging Lake tunnel T2 - TRB 92nd Annual meeting N2 - Tunnel lining evaluation is performed in the Hanging Lake Tunnel near Glenwood Springs, Colorado, using variations of four nondestructive evaluation (NDE) methods: air- and ground-coupled ground penetrating radar (GPR), ultrasonic echo (US echo), ultrasonic tomography (UST), and impact echo (IE). Potential regions of interest are identified using high-speed air-coupled GPR and visual inspection. A robotic frame with pneumatically-operated vacuum plates was used to automate the ground-coupled GPR, US echo, and IE tests, while the UST technique was used manually. This study shows that a particular combination of NDE techniques is a powerful tool for assessing the condition of tunnel linings and can detect potential anomalies such as delamination, depth of surface cracks, reinforcement depth and layout, and lining thickness. By mapping the phase shift of the ultrasonic pulses at detected interface, the potential bonding of layer interfaces and reinforcement is assessed. T2 - TRB 92nd Annual meeting CY - Washington, D.C., USA DA - 13.01.2013 KW - Nondestructive evaluation KW - Concrete KW - Ultrasonic KW - GPR KW - Impact echo PY - 2013 UR - http://trid.trb.org/view.aspx?id=1241994 SP - 1 EP - 16 AN - OPUS4-32027 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -