Below is the uncorrected machine-read text of this chapter, intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text of each book. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.
C-1Â Â A P P E N D I X C Nondestructive Evaluation Technology Maturity and Gap Assessment This document presents the maturity assessment of the technologies identified in Chapter 4 in the report. Some of the technologies identified in Chapter 4 were excluded from the table because they are old or legacy technologies that have a very limited possibility of improvement, or they are at a very early stage and only reported in isolated studies with no sufficient evidence of their applicability for future widespread application. It is important to note that the maturity scores are based on the technologyâs applicability to the asset type and the corresponding application. Therefore, some of the mature technologies may be scored at a lower maturity level because they need enhancement for that specific application A gap in technology maturity can be defined as the difference between the current maturity level and the highest maturity level to be achieved. Therefore, the maturity assessment provided in this appendix captures the gaps in the technologies. In addition to the scores, comments were added to the maturity assessment tables to explain some of the specifics related to the gaps and the potential for the technology to improve the foundation condition assessment capabilities if developed appropriately.
Table C-1. Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Falling Weight Deflectometer (FWD) Pavements Deflection Strength/stiffness parameters, stress and strain responses to traffic, voids under rigid pavements (estimated from responses) Cracking 5 4 6 4 2 Rutting 2 HW: There is a need to improve the collection speed. Robustness of the system and integration with other technologies. Depressions 2 EF: There are many assumptions involved in the analysis and changes can affect the analysis outputs. Faulting 1 Traffic Speed Deflectometer Devices (TSDDs) Pavements Deflection Strength/stiffness parameters/stress and strain responses to traffic Cracking 3 3 1 1 1 HW: Due to the limitations of EF and SW, the designs can be improved to infer better parameters. Rutting 1 EF: There is a need to improve the models inferring the layersâ parameters from the pavement response to a moving load. Depressions 1 SW: The software only provides a data output but there is limited knowledge on how to use the data and incorporate it in predicting and assessing the foundational capacity of pavements. Faulting 1 The device presents great potential for network data collection. We identified multiple potential problem statements and selected the most critical eight.
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Surface Waves Analysis Pavements Propagating Stress Waves Strength/stiffness parameters Cracking 3 6 3 3 1 HW: There is no automated system; the data collection can be time-consuming and needs specialized training. The procedure and how the test is performed can impact the reliability of the results. Rutting 1 SW: There is a need to improve the interpretation of the results and extract parameters. Depressions 1 TIML (layer thickness): Reliability depends on the contrast in the properties between the different layers. GPR is a better tool and can be more sensitive to the different layers. Layer thickness Varies 1 Potential Problem Statement: To work on processing and interpretation. Culverts Voids and bedding of surrounding geomaterials (in limited cases) Loss of confinement/ support and geomaterial erosion 2 6 3 2 1 Delamination Reinforcement corrosion 2 Corrosion cannot be detected directly but can be inferred from delamination. Embankments Produce profiles of geomaterial layers 3 6 3 3 2
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Ground Penetrating Radar (GPR) Pavements Dielectric Constant Layer thickness, presence of moisture Varies 6 6 4 4 3 It can measure/indicate anomalies and not directly related to the mentioned conditions. GPR (from the surface) Culverts Dielectric Constant Location and size Bedding voids in surrounding geomaterials Loss of confinement/ support and geomaterial erosion 6 6 4 4 1 Can detect voids near the surface; however, beddings can be very challenging. GPR (from a nonmetallic culvert) Culverts Dielectric Constant Location and size Bedding voids in surrounding geomaterials Loss of confinement/ support and geomaterial erosion 5 6 4 4 2 Ground Penetrating Radar (GPR) MSE Walls Dielectric Constant Voids and caving-in geomaterials behind the facing Voids and caving in geomaterials 6 6 4 4 2 Groundwater presence Increase in water pressure or volume NA Can detect the groundwater level but not the water pressure and volume; therefore, parameters cannot be inferred directly. Increase in earth pressure loads NA Adjacent construction influence NA Extreme events NA GPR (above presence of groundwater) Embankments Dielectric Constant Seepage flow rate Varies 6 6 4 4 2
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Air-Launched or Ground- Coupled Ground Penetrating Radar (GPR) Tunnels Dielectric Constant Tile debonding Material deterioration due to corrosion or material degradation over time 6 6 4 4 2 Extreme events 2 Delamination Material deterioration due to corrosion or material degradation over time 2 Extreme events 2 Voids in the geomaterials behind the lining Voids behind and within tunnel linings 1 Extreme events 1 Voids in the tunnel linings Voids behind and within tunnel linings 2 Extreme events 2
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall LiDAR Bridges 3D Location of Points on the Surface (Point Cloud) Vertical and lateral deformations Time-related changes in geomaterial foundation material support (strength, modulus) 5 6 4 4 3 SW: The software tools for rendering and displaying the point clouds and finding direct measurements are mature; however, the gap is in the tools that process the point clouds automatically to infer information related to the infrastructure condition. Adjacent construction influence 3 Loss of support due to voids/caving 3 Extreme events 3 LiDAR Culverts 3D Location of Points on the Surface (Point Cloud) Embankment, road surface, and global deformation Differential settlement and joint misalignment 5 6 4 4 1 Culvert alignment issues 1 Differential settlement Differential settlement and joint misalignment 1
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall LiDAR MSE Walls 3D Location of Points on the Surface (Point Cloud) Local or global vertical, lateral, and rotational deformations Excessive deformation 5 6 4 4 2 Time-related changes in geomaterial and foundation material support 1 The analysis procedure and software tools can be improved and automated. Adjacent construction influence 3 Data management can be challenging; however, more solutions are available and are being developed. Extreme events 3 Potential Problem Statement: To relate deformations measured using LiDAR to changes in geomaterial and foundation material support. Facing deterioration (spalling, cracks) Corrosion and deterioration of reinforcements or facing components 1 LiDAR Soil Nails 3D Location of Points on the Surface (Point Cloud) Local or global vertical, lateral, and rotational deformations Excessive deformation 5 6 4 4 3 Adjacent construction influence 2 Extreme events 1
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall LiDAR Cantilever and Ground Anchor Walls 3D Location of Points on the Surface (Point Cloud) Local or global vertical, lateral, and rotational deformations Excessive deformation 5 6 4 4 2 Noncontact Remote Sensing like InSAR, LiDAR, Aerial and Surface Photogrammetry Embankments 3D Location of Points on the Surface (Point Cloud) Deformation at the surface (local and global; vertical and lateral) Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 6 6 5 5 2 Adjacent construction influence 2 Extreme events 2
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration TDML TIML Comments HW EF SW Overall Noncontact like InSAR, LiDAR, Aerial and Surface Photogrammetry Rock Cuts 3D Location of Points on the Surface (Point Cloud) Surface condition (e.g., scratches and scars) Rock fracture infiltration 6 6 5 5 2 Material disintegration 2 Extreme events 2 Surface deformation Material disintegration 2 Extreme events 2 Fissures Rock fracture infiltration 2 Material disintegration 2 Extreme events 2 Rock disintegration Material disintegration 2 Extreme events 2 Noncontact like InSAR, LiDAR, Aerial and Surface Photogrammetry Soil Cut Slopes 3D Location of Points on the Surface (Point Cloud) Deformation at the surface (vertical and lateral) Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 6 6 5 5 2 Adjacent construction influence 2 Extreme events 2 Automated Total Station (surveys) Bridges Location of Points on the Surface Vertical and lateral deformations Time-related changes in geomaterial foundation material support (strength, modulus) 6 6 6 6 3 Adjacent construction influence 3 Loss of support due to voids/caving 3 Extreme events 3
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Closed-Circuit Television (CCTV)/ Optical Scanning Culverts Images Cracks Cracking 6 6 6 6 3 Spalls Reinforcement corrosion 2 Joint misalignment and separation Joint separation 3 Differential settlement and joint misalignment 3 Dents and localized damage Abrasion and loss of wall thickness 1 Crown sag Cross section deformation 3 Slabbing Cross section deformation 3 Stains from reinforcement corrosion Reinforcement corrosion 3
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Laser Profiling (2D and 3D) Culverts Location of Points on the Inner Surface Culvert alignment issues Culvert alignment issues 6 6 6 6 1 Cracking 1 Joint misalignment and separation Joint separation 1 Differential settlement and joint misalignment 1 Spalls Reinforcement corrosion 1 Ovality and cross- section deformation Cross section deformation 1 There have been recent developments combining laser profiling and video imaging into an integrated system. Invert erosion/corrosion Invert erosion/corrosion 1 Dents and localized damage Abrasion and loss of wall thickness 1 Crown sag Cross section deformation 1 Slabbing Cross section deformation 1 Differential settlement Differential settlement and joint misalignment 1
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration TDML TIML Comments HW EF SW Overall Integrated Systems Which Includes LiDAR, Imaging, and Thermography (e.g., SPACETEC TS3 and mobile truck) Tunnels 3D Location of Points on the Surface (Point Cloud), Images, Temperature Water leakage (IR) Groundwater conditions 5 6 4 4 3 Material deterioration due to corrosion or material degradation over time Extreme events Spalling (LiDAR, imaging) Material deterioration due to corrosion or material degradation over time Extreme events Tile Debonding (IR) Material deterioration due to corrosion or material degradation over time Extreme events Tunnel deformations (LiDAR, imaging) Time-related changes in geomaterial foundation material support (strength, modulus) Adjacent loads and vibrations Extreme events Cracking (imaging) Material deterioration due to corrosion or material degradation over time Extreme events Voids in the geomaterials behind the lining (IT in limited situations) Voids behind and within tunnel linings Extreme events Deformations (LiDAR) Material deterioration due to corrosion or material degradation over time Extreme events Significant mass fall from arch (imaging)
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Infrared Camera MSE Walls Temperature Voids and caving-in geomaterials behind the facing 6 6 6 6 1 Groundwater presence Increase in water pressure or volume NA Increase in earth pressure loads NA Adjacent construction influence NA Extreme events NA Embedded Sensors for Material Deterioration Rate Bridges Varies Reinforcement steel and metallic membersâ corrosion rate Deep foundationsâ Installation integrity defects (voids, driving damage, soft tip bearing) 2 2 1 1 1 Potential Problem Statement: Improve the interpretation and use of corrosion rates on the deterioration and foundational capacity of assets. Extreme events 1 Concrete disintegration/ degradation Deep foundationsâ Installation integrity defects (voids, driving damage, soft tip bearing) 1 Extreme events 1
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Embedded Sensors Including MEMS (microelectromechanical systems), TDR (time domain reflectometry), Fiber Optics Distributed Measurement, Piezometers, Thermal Sensors, Stress Cells, Tensiometers, Moisture Content Sensors, Thermistor Pavements Varies Moisture content Cracking 6 6 6 6 NA Moisture content is more of a warning sign, and there is no direct application/ not typically used to assess deterioration. Rutting Bumps Depressions Potholes Roughness Punchouts Pumping Faulting Pore water pressure Cracking NA Rutting Bumps Depressions Potholes Roughness Punchouts Pumping Frost depth/ temperature profiles versus depth Bumps 1 Potholes 1 Roughness 1 Punchouts 1 Faulting 1 Stress and strain responses to traffic Cracking 3 Rutting 3 Depressions 3 Roughness 3 Punchouts 3 Faulting 3
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration TDML TIML Comments HW EF SW Overall Embedded Sensors for Scour Depth Bridges Varies Scour depth Scour 6 6 3 3 2 Extreme events 2 Point Sensors like Inclinometers, Settlement Points, Tilt Meters, Piezometers. Embedded Sensors Including MEMS (microelectromechanical systems), TDR (time domain reflectometry), Fiber Optics Distributed Measurement, Piezometers, Thermal Sensors, Stress Cells, Tensiometers, Moisture Content Sensors, Thermistor Embankments Varies Deformation at the surface (vertical and lateral) Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 6 6 6 6 3 Adjacent construction influence 3 Extreme events 3 Deformation below ground surface Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 3 Adjacent construction influence 3 Extreme events 3 Pore water pressures Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 3 Adjacent construction influence 3 Extreme events 3
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Point Sensors like Inclinometers, Settlement Points, Tilt Meters, Piezometers Rock Cuts Deformations Surface deformation Material disintegration 6 6 6 6 3 Extreme events 3 Point Sensors like Inclinometers, Settlement Points, Tilt Meters, Piezometers Soil Cut Slopes Deformations, and Pore Water Pressure Deformation at the surface (vertical and lateral) Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 6 6 6 6 3 Adjacent construction influence 3 Extreme events 3 Pore water pressures Erosion 3 Adjacent construction influence 3 Extreme events 3
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Pressure and Strain Sensors Bridges Pressure and Strain Applied loads and moments increased Time-related changes in geomaterial foundation material support (strength, modulus) 6 6 5 5 2 Adjacent construction influence 2 Extreme events 1 Potential Problem Statement: How to install sensors and use them to monitor for extreme events and extreme loads. Vertical and lateral deformations Time-related changes in geomaterial foundation material support (strength, modulus) 2 Foundation material deterioration due to corrosion or material degradation over time 1 Adjacent construction influence 1 Loss of support due to voids/caving 2 Extreme events 1
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Piezometers Bridges Pore Water Pressure Pore water pressure increase (reduced effective stress) Time-related changes in geomaterial foundation material support (strength, modulus) 6 6 6 6 3 Adjacent construction influence 3 Extreme events 3 Inclinometers/ Vertical and Horizontal Deformation Sensors (Including the Recent Versions) Bridges Deformations Vertical and horizontal deformations Time-related changes in geomaterial foundation material support (strength, modulus) 6 6 6 6 2 Foundation material deterioration due to corrosion or material degradation over time 2 Adjacent construction influence 2 Loss of support due to voids/caving 1 Extreme events 2 Tilt Sensors and Accelerometers Signs and Masts Foundations Deformations angle of rotation Rotational failure of foundations 6 6 6 6 NA Very limited to no mention of NDE evaluation for foundations. Lateral deformation Reduction of lateral resistance due to repeated lateral loading/material softening Potential Problem Statement: Use of sensors to assess impacts of repeated lateral loads on foundational conditions.
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Long-Gage Fiber Bragg Grating (LGFBG) Sensing Array Soil Nails Varies Reinforcement corrosion and grout integrity Increase in earth pressure loads 4 3 1 1 1 Corrosion and deterioration of reinforcements or facing components 1 Extreme events 1 Voids and caving-in geomaterials behind the facing Extreme events 1 Reinforcement pullout Corrosion and deterioration of reinforcements or facing components 1 Extreme events 1 Optical-fiber Sensors (OFSs) for Monitoring the Strain and Temperature Distribution of Glass Fiber Reinforced Polymer (GFRP)/Brillouin Optical Time Domain Analysis (BOTDA). Soil Nails Varies Reinforcement corrosion and grout integrity Increase in earth pressure loads 4 3 1 1 1 Corrosion and deterioration of reinforcements or facing components 1 Extreme events 1 Reinforcement pullout Corrosion and deterioration of reinforcements or facing components 1 Extreme events 1
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall DFOS Cantilever and Ground Anchor Walls Strain and Temperature Reinforcement strain (relates to load transfer) Increase in earth pressure loads 4 3 1 1 1 There is a gap in the procedures and software tools to assess the condition from acquired data. Potential Problem Statement: To improve the analytical procedures to assess the condition of retaining systems. DFOS Soil Cut Slopes Strain and Temperature Deformation Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 4 3 1 1 1 There is a gap in the procedures and software tools to assess the condition from acquired data. Potential Problem Statement: To improve the analytical procedures to assess the condition of retaining systems. Adjacent construction influence 1 Extreme events 1 High-Resolution Fiber Optic Sensor Tunnels Strain and Temperature Deformations Material deterioration due to corrosion or material degradation over time 4 3 1 1 1 Potential Problem Statement: Use of fiber optic sensors to monitor deformation and related foundation conditions. Extreme events Delamination Reinforcement corrosion 2 Cannot detect corrosion directly but can be inferred from delamination.
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/ Deterioration TDML TIML Comments HW EF SW Overall Linear Polarization Resistance (LPR) MSE Walls Polarization Resistance Corrosion deterioration rate Corrosion and deterioration of reinforcements or facing components 5 5 2 2 1 Electrochemical Impedance Spectrometry MSE Walls Impedance of the Metal Over a Wide Range of Frequencies Corrosion deterioration rate Corrosion and deterioration of reinforcements or facing components 5 5 2 2 1 Coupon Testing MSE Walls Corrosion of Coupon Corrosion deterioration rate Corrosion and deterioration of reinforcements or facing components 6 6 6 6 1 The test procedure requires access and coring from constructed walls and it is not the most favorable technique and can be considered partially destructive. Resistivity Imaging (RI) MSE Walls Electric Current Resistivity Groundwater presence Increase in water pressure or volume 6 6 4 4 NA Can detect the groundwater level but not the water pressure and volume. Increase in earth pressure loads NA Adjacent construction influence NA Extreme events NA Linear Polarization Rock Cuts Polarization Resistance Rock bolts corrosion and integrity Extreme events 5 5 2 2 2
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration TDML TIML Comments HW EF SW Overall Electrical Resistivity Soil Cut Slopes Electric Current Resistivity Change in water content leading to loss of strength Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 6 6 4 4 2 Extreme events 2 Various Surface and Down-Hole Geophysical Methods Bridges Varies Embedded foundation geometry Scour 4 4 2 2 2 Loss of support due to voids/caving 2 Extreme events 2 Voids and caving in geomaterials Scour 2 Foundation material deterioration due to corrosion or material degradation over time 1 Adjacent construction influence 2 Loss of support due to voids/caving 2 Extreme events 2
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration TDML TIML Comments HW EF SW Overall Ultrasonic/ Impact- Echo/ High- Frequency Surface Waves Culverts Stress Waves Dents and localized damage (large size) Abrasion and loss of wall thickness 4 6 3 3 1 HW: Accessibility challenges given the system size and procedures. Delamination Reinforcement corrosion 2 This is already an active research area with significant research studies funded by different agencies, Other localized concrete defects (honeycombing, voids, etc.) Other localized concrete defects (honeycombing, voids, etc.) 2 Cracking and material deterioration 2 Sonic Echo Method Soil Nails Reflected Time of Compression Wave Reinforcement corrosion Corrosion and deterioration of reinforcements (nails) 4 5 2 2 1 Length of in-service soil nails Length of in-service soil nails 2 Impulse Response Test Soil Nails Mechanical Impedance of Soil Nails Grout Integrity 4 4 2 2 1 Impact and Ultrasonic Testing (tendons condition) Rock Cuts Propagation Velocity of Body Waves Rock bolts corrosion and integrity Extreme events 4 5 2 2 2
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration TDML TIML Comments HW EF SW Overall Ultrasonic Tomography Tunnels Travel Time of Ultrasonic Waves Over a Large Array of Sensors Delamination Material deterioration due to corrosion or material degradation over time 6 6 4 4 1 Extreme events 1 Voids in the tunnel linings Voids behind and within tunnel linings 1 Extreme events 1 Ultrasonic Surface Waves and Impact- Echo Tunnels Propagation Velocity and Reflection of High- Frequency Waves Delamination Material deterioration due to corrosion or material degradation over time 4 6 4 4 2 Extreme events 2 Voids in the tunnel linings Voids behind and within tunnel linings 1 Extreme events 1 Acoustic Emission (AE) Techniques/ Distributed Acoustic Sensors Soil Cut Slopes Ultrasonic Stress Waves due to Deformations Deformation at the surface (vertical and lateral) Time-related changes in geomaterial and foundation material supporting the embankment (including delayed effects of consolidation) 4 5 4 2 1 Hardware is expensive. Adjacent construction influence Extreme events
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration No Technology MSE Walls NA Geomaterial shear strength reduction and geomaterial modulus reduction Time-related changes in geomaterial and foundation material support MSE Walls Reinforcement rupture and reinforcement pullout Reinforcement rupture and reinforcement pullout Soil Nails Applied loads and moments increased Groundwater levels Geomaterial shear strength reduction Geomaterial modulus reduction Pore water pressure increase (changes in effective stresses) Reinforcement rupture Cantilever and Ground Anchor Walls Increase in earth pressure loads Applied loads and moments increased Groundwater levels Pore water pressure behind the wall and at base level Reinforcement rupture (changes load distribution on the wall/facing) Reinforcement pullout (changes load distribution on the wall/facing) Corrosion and deterioration of reinforcements or facing components Corrosion and deterioration of facing components Reinforcement rupture Reinforcement pullout Increase in water pressure or volume Groundwater levels Pore water pressure increase (changes in effective stresses)
Table C-1 (Continued). Maturity and gap assessment of NDE technologies. Technology Asset Measured Parameter(s) Inferred Parameter Condition/Deterioration No Technology Cast-in-Place Walls All related conditions Embankments Measurements of strength and deformation behavior Rock Cuts Measurements of strength or deformation properties Soil Cut Slopes Seepage flow rate Cavities and conduits Tunnels Strength and stiffness parameters Groundwater conditions Moisture content Pore water pressure Material deterioration due to corrosion or material degradation over time Concrete permeability Reinforcing steel corrosion Corrosion of steel liners Adjacent loads and vibrations In situ stresses in surrounding geomaterials
