NDEs are conducted using a variety of modalities and therefore presented in a variety of data formats. Even within each modality, the data format often varies requiring special proprietary software to access, review and archive. This presents a long-term issue for asset owners or others who are responsible for maintaining records.

An American Society for Testing Materials (ASTM) standard exist for governing the digital imaging and communications of advance nondestructive evaluations but is seldom required by contracting authorities for either

1. equipment/manufacturer are not compliant or
2. the modality has not been outlined to meet the ASTM standard yet.

DICONDE (Standard Practice for Digital Imaging and Communication in Nondestructive Evaluation) is an ASTM standard (E2339) ⁽¹⁾ that mirrors the Digital Imaging and Communication in Medicine (DICOM) standard for the medical field to help “facilitate the interoperability of NDE imaging and data acquisition equipment by specifying the image data in commonly accepted terms. This standard represents a harmonization of NDE imaging systems, or modalities, with the National Electrical Manufacturers Association (NEMA) Standards Publication titled Digital Imaging and Communications in Medicine, an international standard for image data acquisition, review, storage and archival. In addition, this standard provides a set of industrial NDE specific information object definitions, which travel beyond the scope of standard DICOM modalities. The goal of this standard is to provide means by which NDE image/signal data may be displayed on by any system conforming to the ASTM DICONDE format, regardless of which NDE modality was used to acquire the data” (ASTM E2339 scope). This standard covers multiple NDE modules such as DRT, CT, DR, Ultrasonic Testing (UT), IR and ET but others could be further developed. However, to date this standard has only really been adopted by the digital radiography community.

Research is needed to further develop modules for IE, GPR, AE, etc. or include addendums for Department of Transportation (DOT) specific needs. Having a standardized format such as DICONDE in which NDE data can be acquired, reviewed, and archived would benefit the use of advanced NDE methods utilizing digital imaging by means of streamlining approvals.

Scope of Work:

1. Conduct a complete review of the DICONDE standards.
2. Explore the possibilities to integrate DICONDE standards into existing practice.  
3. Develop additional modules if necessary and conduct literature review and survey to identify which technologies come in DICONDE complaint format and what other industries are using these standards.
    

References

1. Standard Practice for Digital Imaging and Communication in Nondestructive Evaluation. 2021. doi: 10.1520/E2339-21.

The architecture of existing asset management systems for transportation infrastructure has not been expanded to include the wide assortment of data inputs that can be generated using nondestructive testing (NDT). As such, there is a need to categorize and relate nondestructive data sources to viable input parameters that can be accepted and used by asset management systems. Moreover, there is a need to validate the value that nondestructive data offers, relative to the cost and performance of maintaining assets in a state of good repair through the use of asset management systems for transportation infrastructure.

This research will look at bridge data sources generated by NDT systems, including the types (e.g., textual, numeric, categorial, continuous, etc.) and the volume of data collected. Each data source will be described, including the rationale for its collection for asset management purposes and how the data informs decision-making processes over the life of each asset or asset sub-component. Included in this study will be an assessment of the types of meta-data collected for each nondestructive system and its relation to the physical asset for which the data was collected. The usage of data from each nondestructive system will be studied and evaluated in the context of asset management and performance metrics, with particular focus on how decisions are influenced through the study of nondestructive data.

Additionally, this research will look at the architecture of existing asset management systems to quantify how new data sources might be adopted and utilized. It will be important to understand where, when and to what level nondestructive data can and should be implemented into asset management systems, and the benefits that might be derived through its use for the management of an overall network. Nondestructive data can be integrated into asset management systems in one of three stages, either the input, modeling, or output stage. This research will look at each data stream to understand its best point of entry into the overall asset management plan.

Scope of Work:

1. Perform a literature review on the current practice for integrating NDE into asset management systems of transportation infrastructures, including bridges, pavements, and others.
2. Pinpoint how the use of NDE can inform the decision-making process in asset management.
3. Collect cost information for procuring the NDE service.
4. Evaluate the value of information, in terms of economic costs, provided by the NDE service.

Identify data management strategies before, during, and after the NDE service.

The deliverable from this research will serve as a roadmap for future advances in asset management systems and how these systems may leverage the data-rich content provided through NDT systems.

Use of modern NDE technologies often relates to increased number of data points. There is potential through the process of data fusion that a more intelligent analysis could be conducted. This can occur through data collected from multiple NDE modalities or a single modality in which is data collected multiple times. In the case of highway transportation infrastructure data fusion requires additional research to define guidance on usage and applicable cost benefits.

The challenge for assets owners with implementing data fusion is knowing when/where implementation would be effective and how effective the results would be in helping to make decisions that are cost efficient. Largely, this area of data fusion has not been explored by state highway owners and often gets intermixed with data combination which is a separate area of study. Actively researching this field by soliciting input from owners and validated data would be beneficial to automate the data fusion process with machine learning and deep learning features for repeat assessments.

The objective of this research is to gain an understanding how NDE data fusion could benefit highway asset owners. The infancy of the topic requires some initial research for guidance and return on invest.

Scope of Work:

1. Perform a literature review and develop a report on guidance for implementation.
2. Elicit the help of asset owners to understanding of the needs.
3. Assess when it would be appropriate to implement data fusion into the management of the asset.
4. Provide models for cost effectiveness and benefits to implementation.
5. Estimate the funding and research period.

NDE techniques are increasingly being utilized for the inspection of various reinforced concrete elements of highway bridges. Successful implementation of the nondestructive evaluation methods for bridge inspection requires proper collection, processing, presentation, and interpretation of the collected NDE data.

The objective of this study is to develop QC/QA procedures for NDE data, considering data collection, processing, presentation, and interpretation to ensure all the collected data meet minimum utility requirements. For example, during impact echo data collection, care must be taken that individual waveforms conform to a periodic wave format, and are not the results of accidental impact, etc.

The focus of this study is to define, establish, and prescribe QC/QA processes for commonly used NDE techniques, including:

1. Impact Echo (IE)
2. Ultrasonic Surface Wave (USW)
3. Ground Penetrating Radar (GPR)
4. Electrical Resistivity (ER)
5. Half Cell Potential (HCP)
6. Ultrasonic Methods (UPV and tomography-type)
7. Impulse Response
8. Magnetic Methods (e.g., MFL, pacholometer)

For test methods for which a current ASTM or equivalent standard exists, the provisions of the governing standard shall be followed in all phases of the project from data collection to data interpretation. Impact echo, UPV, ER, and HCP have active ASTM. All NDE data need to be validated using destructive probing, physical measurements, or reliable as-built documentation.

Scope of Work:

For each listed NDE technique:

1. summarize existing standards and specifications (e.g., ASTM, American Association of State Highway and Transportation (AASHTO), American Concrete Institute (ACI), and others) for QC/QA.
2. identify QC/QA challenges in published literature.
3. develop new or improve existing procedures for QC/QA.

With the application of NDE methods for bridges and other transportation structures, consistent, accurate interpretation and communication of the complex results are the most crucial steps for implementing the corrective actions. They allow owners to make informed decisions regarding the future maintenance of those structures and the associated urgency in addressing them.

Often the results of NDE methods need to be converted to the same metrics used by the DOTs, typically, either the general condition ratings for the routine National Bridge Inspection Standards (NBIS) inspections or element-based condition state inspections or both. This could involve separation of the resulting data into discrete qualitative or quantitative bins with commonly accepted ranges or project-specific threshold values. However, there are questions regarding this interpretation of NDE results, especially since a lack of guidance on this procedure leads to inconsistency between different projects and consultants. Answering this question will involve collection of test results from existing studies and testing to verify them under field conditions.

Visualization of results varies significantly from consultant to consultant since there are no accepted standards for it. Also, there is no guidance on how to prescribe the expectations from contracts for the owners. NDE data can be visualized in several ways, but usually they are shared as binary detection maps or nuanced probability maps. Sharing important details while excluding distracting information is a balancing act that can induce confidence and trust in the data when done well, but proper guidance will be helpful to create consistency across the industry. Also, the quality of data or the confidence in the measurements is often not communicated. For example, with ultrasonic measurements, some data points have very clear frequency peaks whereas some locations can have vague peaks that may be indicative of some concerns with either the data collection process or the integrity of the structural member under evaluation, which needs to be communicated as well.

Since visualization involves human factors, an extensive survey should be conducted with personnel who handle NDE results on the consultant side and those who make decisions for maintenance actions on the owner side.

Scope of Work:

1. Survey both NDE practitioners and DOT staff.
2. Confirm NDE results from multiple practitioners with coring.
3. Develop guidelines for the presentation of results.

Develop recommendations to the DOTs for contract requirements that will lead to accurate and consistent NDE results. This study will benefit greatly by creating a consensus on the interpretation of NDE results and by creating guidance on beneficial ways to visualize them.